justinhartman · January 17, 2024 00:46 · Aug 31, 2021 · Aug 26, 2021 · Aug 26, 2021 · Aug 26, 2021
diff --git a/03_install-lemp.md b/03_install-lemp.md
@@ -42,6 +42,7 @@ $ sudo apt -y install lsb-release apt-transport-https ca-certificates wget
 $ wget -O /etc/apt/trusted.gpg.d/php.gpg https://packages.sury.org/php/apt.gpg
 $ echo "deb https://packages.sury.org/php/ $(lsb_release -sc) main" | sudo tee /etc/apt/sources.list.d/php.list
 $ sudo apt update
+$ sudo apt install curl unzip zip
 $ sudo apt -y install php8.0-{fpm,cli,apc,bcmath,bz2,curl,gd,imagick,intl,memcached,mbstring,mysql,redis,xml,zip}
 $ sudo systemctl start php8.0-fpm
 $ sudo systemctl enable php8.0-fpm

diff --git a/04_configure-php-nginx.md b/04_configure-php-nginx.md
@@ -81,6 +81,10 @@ emergency_restart_interval=1m
 process_control_timeout=10s
 ```
 
+```console
+$ sudo systemctl reload php8.0-fpm
+```
+
 ## Configure nginx
 
 ```console
@@ -90,7 +94,7 @@ $ sudo nano /etc/nginx/nginx.conf
 Change these values:
 
 ```nginx
-client_max_body_size 128M;
+client_max_body_size 256M;
 keepalive_timeout 2;
 server_tokens off;
 ```

diff --git a/06_fine-tune-mysql.md b/06_fine-tune-mysql.md
@@ -23,6 +23,19 @@ $ ulimit -Hn
 65535
 ```
 
+Alternatively, you could set system-wide file and process limits with the following configuration:
+
+```ini
+# /etc/security/limits.conf
+# Added to increase server limit of 1024 per process.
+*               soft    nofile          102400
+*               hard    nofile          102400
+*               soft    nproc           10240
+*               hard    nproc           10240
+```
+
+**NB: Your milage may vary so please only use the above with caution!**
+
 ## Setting Swappiness on Linux for MariaDB
 
 ```console
@@ -61,20 +74,20 @@ $ sudo nano /etc/mysql/my.cnf
 ```ini
 # /etc/mysql/my.cnf
 [mysqld]
+open_files_limit               = 102400
 innodb_buffer_pool_size        = 3G
 # innodb_buffer_pool_instances   = 4 (default is 1)
 innodb_flush_log_at_trx_commit = 0
 innodb_flush_method            = O_DIRECT
-
-innodb_log_file_size           = 256M
-max_connections                = 500
-# (50 + max_connections/5)
-back_log                       = 150
-max_allowed_packet             = 32M
+innodb_log_file_size           = 1G
+max_connections                = 5000
+# back_log = (max_connections/5) + 50
+back_log                       = 1050
+max_allowed_packet             = 256M
 # Disable query cache
 query_cache_type               = OFF
 query_cache_size               = 0
 slow_query_log                 = ON
 long_query_time                = 1
-# slow_query_log_file            = /var/lib/mysql/hostname-slow.log
+slow_query_log_file            = /var/lib/mysql/slow.log
 ```
diff --git a/11_install-redis-memcached.md b/11_install-redis-memcached.md
@@ -4,6 +4,8 @@
 
 ```console
 $ sudo apt install redis-server
+$ sudo systemctl start redis-server
+$ sudo systemctl enable redis-server
 ```
 
 ### Edit Configuration
@@ -24,15 +26,16 @@ bind 127.0.0.1 ::1
 ### Restart Redis
 
 ```console
-$ sudo systemctl restart redis
-$ sudo systemctl status redis
+$ sudo systemctl restart redis-server
+$ sudo systemctl status redis-server
 ```
 
 ## Install Memcached
 
 ```console
 $ sudo apt install memcached libmemcached-tools
-$ sudo systemctl status memcached
+$ sudo systemctl start memcached
+$ sudo systemctl enable memcached
 ```
 
 ### Edit Configuration

diff --git a/12_install-composer-node-npm.md b/12_install-composer-node-npm.md
@@ -16,14 +16,8 @@ $ php -r "unlink('composer-setup.php');"
 Composer will be installed at `/usr/local/bin/composer` and you can test the installation as follows:
 
 ```console
-$ /usr/local/bin/composer -v
-   ______
-  / ____/___  ____ ___  ____  ____  ________  _____
- / /   / __ \/ __ `__ \/ __ \/ __ \/ ___/ _ \/ ___/
-/ /___/ /_/ / / / / / / /_/ / /_/ (__  )  __/ /
-\____/\____/_/ /_/ /_/ .___/\____/____/\___/_/
-                    /_/
-Composer version 2.0.8 2020-12-03 17:20:38
+$ /usr/local/bin/composer -V
+Composer version 2.1.6 2021-08-19 17:11:08
 ```
 
 If you get an error output stating `Installer corrupt`, it means the version of composer has been updated and you'll need a new hash. Visit the official [getcomposer.org download page][compser] to get the latest `hash_file` string and/or install via that method.
@@ -43,9 +37,9 @@ Test the installation:
 
 ```console
 $ node -v
-v12.20.0
+v12.22.5
 $ npm -v
-6.14.8
+6.14.14
 ```
 
 ### Install Yarn
@@ -62,7 +56,7 @@ You can test it out with:
 
 ```console
 $ yarn -v
-1.22.10
+1.22.5
 ```
 
 ### Optional

diff --git a/05_fine-tune-php-fpm.md b/05_fine-tune-php-fpm.md
@@ -98,7 +98,7 @@ pm.max_children = 222
 pm.start_servers = 16
 ; CPU * 2 = 8
 pm.min_spare_servers = 8
-; Same as children
+; Same as start_servers
 pm.max_spare_servers = 16
 pm.max_requests = 500
 ```

diff --git a/05_fine-tune-php-fpm.md b/05_fine-tune-php-fpm.md
@@ -82,7 +82,7 @@ $ sudo nano /etc/php/7.4/fpm/pool.d/www.conf
 [www]
 user = www-data
 group = www-data
-# listen = /run/php/php7.4-fpm.sock
+; listen = /run/php/php7.4-fpm.sock
 listen = /run/php/php8.0-fpm.sock
 listen.owner = www-data
 listen.group = www-data

diff --git a/02_general.md b/02_general.md
@@ -1,6 +1,6 @@
 # General Setup
 
-These are a series of specific commands to configure the Ubuntu server for our environment. You may not need to do these.
+These are a series of specific commands to configure the Debian server for our environment. You may not need to do these.
 
 ```console
 $ sudo apt-get install locales-all
@@ -21,7 +21,7 @@ export LC_TERMINAL=en_GB.UTF-8
 ## Change Timezone
 
 ```console
-$ sudo cp /usr/share/zoneinfo/Africa/Johannesburg /etc/localtime # set time
+$ sudo cp /usr/share/zoneinfo/Europe/London /etc/localtime # set time
 ```
 
 ## Change Hostname
@@ -37,6 +37,6 @@ $ hostnamectl
            Boot ID: dae700b6e5bb44fcb5d4683f05f30919
     Virtualization: vmware
   Operating System: Debian GNU/Linux 10 (buster)
-            Kernel: Linux 4.19.0-12-amd64
+            Kernel: Linux 4.19.0-17-amd64
       Architecture: x86-64
 ```
diff --git a/03_install-lemp.md b/03_install-lemp.md
@@ -34,7 +34,7 @@ mysql> exit
 
 ## Step 3 - Install PHP-FPM
 
-_I've chosen to install PHP 8.0 but you can change any of the commands from `php7.4` to `php8.0` if needed. For example any reference to `php7.4-fpm` can be adjusted simply to `php8.0-fpm`._
+_I've chosen to install PHP 8.0 but you can change any of the commands from `php8.0` to `php7.4` as needed. For example any reference to `php8.0-fpm` can be adjusted simply to `php7.4-fpm`._
 
 ```console
 $ sudo apt-get update
@@ -43,6 +43,6 @@ $ wget -O /etc/apt/trusted.gpg.d/php.gpg https://packages.sury.org/php/apt.gpg
 $ echo "deb https://packages.sury.org/php/ $(lsb_release -sc) main" | sudo tee /etc/apt/sources.list.d/php.list
 $ sudo apt update
 $ sudo apt -y install php8.0-{fpm,cli,apc,bcmath,bz2,curl,gd,imagick,intl,memcached,mbstring,mysql,redis,xml,zip}
-$ sudo systemctl start php8.0-fpm  # or replace with php7.4-fpm
-$ sudo systemctl enable php8.0-fpm  # php7.4-fpm
+$ sudo systemctl start php8.0-fpm
+$ sudo systemctl enable php8.0-fpm
 ```
diff --git a/04_configure-php-nginx.md b/04_configure-php-nginx.md
@@ -20,7 +20,7 @@ Change these values:
 cgi.fix_pathinfo=0
 post_max_size=256M
 upload_max_filesize=256M
-date.timezone=Africa/Johannesburg
+date.timezone=Europe/London
 [opcache]
 opcache.memory_consumption=256
 opcache.max_accelerated_files=50000

diff --git a/07_remove_systemd_limits.md b/07_remove_systemd_limits.md
@@ -50,7 +50,7 @@ TasksMax=infinity
 ## Nginx
 
 ```console
-$ sudo nano /lib/systemd/system/redis-server.service
+$ sudo nano /lib/systemd/system/nginx.service
 [Service]
 TasksMax=infinity
 ```

diff --git a/01_introduction.md b/01_introduction.md
@@ -27,7 +27,7 @@ These documents take you through each step of the configuration from:
 [config]: #file-04_configure-php-nginx-md
 [fpm-tune]: #file-05_fine-tune-php-fpm-md
 [mysql]: #file-06_fine-tune-mysql-md
-[systemd]: #file-07_remove-systemd-process-limits-md
+[systemd]: #file-07_remove_systemd_limits-md
 [vhost]: #file-08_new-vhost-md
 [ssl]: #file-09_setup-ssl-md
 [ssh]: #file-10_ssh-remote-login-md

diff --git a/01_introduction.md b/01_introduction.md
@@ -15,6 +15,7 @@ These documents take you through each step of the configuration from:
 1. [Confiure PHP and Nginx][config]
 1. [How to fine-tune PHP-FPM][fpm-tune]
 1. [Fine-tune MySQL/MariaDB for Performance][mysql]
+1. [Remove systemd process limits][systemd]
 1. [Create a New Nginx Host][vhost]
 1. [Setup Let's Encrypt SSL certificates][ssl]
 1. [Setup Remote SSH Login with sudo][ssh]
@@ -26,8 +27,9 @@ These documents take you through each step of the configuration from:
 [config]: #file-04_configure-php-nginx-md
 [fpm-tune]: #file-05_fine-tune-php-fpm-md
 [mysql]: #file-06_fine-tune-mysql-md
-[vhost]: #file-07_new-vhost-md
-[ssl]: #file-08_setup-ssl-md
-[ssh]: #file-09_ssh-remote-login-md
-[redis]: #file-10_install-redis-memcached-md
-[composer]: #file-11_install-composer-node-npm-md
+[systemd]: #file-07_remove-systemd-process-limits-md
+[vhost]: #file-08_new-vhost-md
+[ssl]: #file-09_setup-ssl-md
+[ssh]: #file-10_ssh-remote-login-md
+[redis]: #file-11_install-redis-memcached-md
+[composer]: #file-12_install-composer-node-npm-md
diff --git a/06_fine-tune-mysql.md b/06_fine-tune-mysql.md
@@ -10,6 +10,8 @@ To increase this, edit `/etc/security/limits.conf` and specify or add the follow
 # Added to increase server limit of 1024 per process.
 mysql            soft    nofile          65535
 mysql            hard    nofile          65535
+# Uncomment this if ulimit doesn't change from 1024
+#*                soft    nofile          65535
 ```
 
 This requires a system restart. Once rebooted, check the limit with:
@@ -75,4 +77,4 @@ query_cache_size               = 0
 slow_query_log                 = ON
 long_query_time                = 1
 # slow_query_log_file            = /var/lib/mysql/hostname-slow.log
-```
+```
diff --git a/07_remove_systemd_limits.md b/07_remove_systemd_limits.md
@@ -0,0 +1,78 @@
+# Remove systemd process limits
+
+There are now also some issues with `systemd` limiting file processes. Have a look at the following:
+
+```console
+$ sudo systemctl status redis-server
+● redis-server.service - Advanced key-value store
+   Loaded: loaded (/lib/systemd/system/redis-server.service; enabled; vendor preset: enabled)
+   Active: active (running) since Sun 2021-08-01 23:24:48 BST; 13min ago
+     Docs: http://redis.io/documentation,
+           man:redis-server(1)
+ Main PID: 571 (redis-server)
+    Tasks: 4 (limit: 4915)
+   Memory: 9.7M
+   CGroup: /system.slice/redis-server.service
+           └─571 /usr/bin/redis-server 127.0.0.1:6379
+```
+
+If you see the `Tasks: 4 (limit: 4915)` has a limit set of 4915. This is how the Linux Kernel works and it defaults to 15%, 
+which equals `4915` with the kernel's defaults on the host.
+
+In order to check what your system is capable of it's a rather easy calculation.
+
+```console
+$ more /proc/sys/kernel/pid_max
+32768
+```
+
+You now take this number and work out 15% of the value, i.e. `32768*15/100 = 4915.2` and you can see how this is calculated.
+
+That said, you can override this for certain Debian-based services and here's how we change them for those services.
+
+## MariaDB
+
+```console
+$ sudo nano /etc/systemd/system/mysqld.service
+[Service]
+TasksMax=infinity
+LimitNOFILE=65535
+```
+
+## PHP
+
+```console
+$ sudo nano /lib/systemd/system/php8.0-fpm.service
+[Service]
+TasksMax=infinity
+```
+
+## Nginx
+
+```console
+$ sudo nano /lib/systemd/system/redis-server.service
+[Service]
+TasksMax=infinity
+```
+
+## Redis
+
+```console
+$ sudo nano /lib/systemd/system/redis-server.service
+[Service]
+TasksMax=infinity
+```
+
+## Memcached
+
+```console
+$ sudo nano /lib/systemd/system/memcached.service
+[Service]
+TasksMax=infinity
+```
+
+## Restarting systemctl
+
+When you're done making these changes you have to restart systemctl with `sudo systemctl daemon-reload` in order for the file 
+limits to be removed.
+
diff --git a/07_new-vhost.md → 08_new-vhost.md b/07_new-vhost.md → 08_new-vhost.md
diff --git a/08_setup-ssl.md → 09_setup-ssl.md b/08_setup-ssl.md → 09_setup-ssl.md
diff --git a/09_ssh-remote-login.md → 10_ssh-remote-login.md b/09_ssh-remote-login.md → 10_ssh-remote-login.md
diff --git a/10_install-redis-memcached.md → 11_install-redis-memcached.md b/10_install-redis-memcached.md → 11_install-redis-memcached.md
diff --git a/11_install-composer-node-npm.md → 12_install-composer-node-npm.md b/11_install-composer-node-npm.md → 12_install-composer-node-npm.md
diff --git a/11_install-composer-node-npm.md b/11_install-composer-node-npm.md
@@ -50,10 +50,12 @@ $ npm -v
 
 ### Install Yarn
 
-With NVM installed you can install `yarn` with the following command:
+To install the Yarn package manager, run:
 
 ```console
-$ npm install -g yarn
+$ curl -sL https://dl.yarnpkg.com/debian/pubkey.gpg | gpg --dearmor | sudo tee /usr/share/keyrings/yarnkey.gpg >/dev/null
+$ echo "deb [signed-by=/usr/share/keyrings/yarnkey.gpg] https://dl.yarnpkg.com/debian stable main" | sudo tee /etc/apt/sources.list.d/yarn.list
+$ sudo apt-get update && sudo apt-get install yarn
 ```
 
 You can test it out with:

diff --git a/08_setup-ssl.md b/08_setup-ssl.md
@@ -70,10 +70,105 @@ $ sudo nginx -t && sudo systemctl reload nginx
 
 ## Renew Certificates
 
-Configure Certbot to reload NGINX when it successfully renews certificates. Run the following commands:
+You will now need to create a post hook script for certbot so that it can reload Nginx once a domain has been renewed. Luckily I have created a script for you to do this and you can [access the script over here](https://git.io/JtMvt). Setting up this script as is a simple 3 step process.
+
+### Step 1
+
+First create the `nginx-reload.sh` post hook file:
+
+```console
+$ sudo nano /etc/letsencrypt/renewal-hooks/post/nginx-reload.sh
+```
+
+### Step 2
+
+You are going to want to copy the [code of the script by clicking here](https://git.io/JtMvt) and head on over and paste it in your `/etc/letsencrypt/renewal-hooks/post/nginx-reload.sh` file.
+
+### Step 3
+
+Once you have the file saved, make it executable and reload nginx.
 
 ```console
-$ echo -e '#!/bin/bash\nnginx -t &>/dev/null && systemctl reload nginx' | sudo tee /etc/letsencrypt/renewal-hooks/post/nginx-reload.sh
 $ sudo chmod a+x /etc/letsencrypt/renewal-hooks/post/nginx-reload.sh
 $ sudo nginx -t && sudo systemctl reload nginx
+```
+
+Done. The script is now setup to begin working automatically in the background. Certbot runs a cronjob twice daily and if a certificate is renewed your newly created post hook script will be executed and run.
+
+### Success Output
+
+Executing the `nginx-reload.sh` file without any errors in any of your `nginx` config or virtual host files will output the following success messages to your console:
+
+```console
+$ sudo /etc/letsencrypt/renewal-hooks/post/nginx-reload.sh
+Removing old log file.
+Success: Reloading nginx server.
+```
+
+Similarly, when the `certbot` cronjob executes and runs this post hook script the following successful output will be seen.
+
+```console
+$ sudo certbot renew
+Saving debug log to /var/log/letsencrypt/letsencrypt.log
+Processing /etc/letsencrypt/renewal/example.com.conf
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Plugins selected: Authenticator webroot, Installer None
+Renewing an existing certificate
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+new certificate deployed without reload, fullchain is
+/etc/letsencrypt/live/example.com/fullchain.pem
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Congratulations, all renewals succeeded. The following certs have been renewed:
+  /etc/letsencrypt/live/example.com/fullchain.pem (success)
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Running post-hook command: /etc/letsencrypt/renewal-hooks/post/nginx-reload.sh
+Output from nginx-reload.sh:
+Removing old log file.
+Success: Reloading nginx server.
+```
+
+### Error Output
+
+Executing the `nginx-reload.sh` file with an error in either your `nginx` config or virtual hosts files will output the following error and log file:
+
+```console
+$ sudo /etc/letsencrypt/renewal-hooks/post/nginx-reload.sh
+Removing old log file.
+Fail: Error with config file.
+Aborting nginx restart.
+Log file output:
+nginx: [emerg] "worker_connections" directive is not allowed here in /etc/nginx/nginx.conf:7
+nginx: configuration file /etc/nginx/nginx.conf test failed
+```
+
+Similarly, when the `certbot` cronjob executes and runs this post hook script the following output will be seen.
+
+```console
+$ sudo certbot renew
+Saving debug log to /var/log/letsencrypt/letsencrypt.log
+Processing /etc/letsencrypt/renewal/example.com.conf
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Plugins selected: Authenticator webroot, Installer None
+Renewing an existing certificate
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+new certificate deployed without reload, fullchain is
+/etc/letsencrypt/live/example.com/fullchain.pem
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Congratulations, all renewals succeeded. The following certs have been renewed:
+  /etc/letsencrypt/live/example.com/fullchain.pem (success)
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Running post-hook command: /etc/letsencrypt/renewal-hooks/post/nginx-reload.sh
+Output from nginx-reload.sh:
+Removing old log file.
+Fail: Error with config file.
+Aborting nginx restart.
+Log file output:
+nginx: [emerg] "worker_connections" directive is not allowed here in /etc/nginx/nginx.conf:7
+nginx: configuration file /etc/nginx/nginx.conf test failed
+
+Hook command "/etc/letsencrypt/renewal-hooks/post/nginx-reload.sh" returned error code 1
 ```
diff --git a/03_install-lemp.md b/03_install-lemp.md
@@ -43,6 +43,6 @@ $ wget -O /etc/apt/trusted.gpg.d/php.gpg https://packages.sury.org/php/apt.gpg
 $ echo "deb https://packages.sury.org/php/ $(lsb_release -sc) main" | sudo tee /etc/apt/sources.list.d/php.list
 $ sudo apt update
 $ sudo apt -y install php8.0-{fpm,cli,apc,bcmath,bz2,curl,gd,imagick,intl,memcached,mbstring,mysql,redis,xml,zip}
-$ sudo systemctl start php8.0-fpm
-$ sudo systemctl enable php8.0-fpm
+$ sudo systemctl start php8.0-fpm  # or replace with php7.4-fpm
+$ sudo systemctl enable php8.0-fpm  # php7.4-fpm
 ```
diff --git a/04_configure-php-nginx.md b/04_configure-php-nginx.md
@@ -8,6 +8,12 @@ These are the different configuration files for setting up the servers.
 $ sudo nano /etc/php/8.0/fpm/php.ini
 ```
 
+OR for PHP 7.4:
+
+```console
+$ sudo nano /etc/php/7.4/fpm/php.ini
+```
+
 Change these values:
 
 ```ini
@@ -63,6 +69,12 @@ $ sudo systemctl reload php8.0-fpm
 $ sudo nano /etc/php/8.0/fpm/php-fpm.conf
 ```
 
+OR for PHP 7.4:
+
+```console
+$ sudo nano /etc/php/7.4/fpm/php-fpm.conf
+```
+
 ```nginx
 emergency_restart_threshold=10
 emergency_restart_interval=1m

diff --git a/05_fine-tune-php-fpm.md b/05_fine-tune-php-fpm.md
@@ -72,10 +72,17 @@ Change the `www` pool so it now has the following settings.
 $ sudo nano /etc/php/8.0/fpm/pool.d/www.conf
 ```
 
+OR for PHP 7.4:
+
+```console
+$ sudo nano /etc/php/7.4/fpm/pool.d/www.conf
+```
+
 ```ini
 [www]
 user = www-data
 group = www-data
+# listen = /run/php/php7.4-fpm.sock
 listen = /run/php/php8.0-fpm.sock
 listen.owner = www-data
 listen.group = www-data
@@ -99,7 +106,7 @@ pm.max_requests = 500
 Reload PHP:
 
 ```console
-$ sudo systemctl reload php8.0-fpm
+$ sudo systemctl reload php8.0-fpm # or replace with php7.4-fpm
 ```
 
 [tuning]: https://tideways.com/profiler/blog/an-introduction-to-php-fpm-tuning

diff --git a/06_fine-tune-mysql.md b/06_fine-tune-mysql.md
@@ -57,6 +57,7 @@ $ sudo nano /etc/mysql/my.cnf
 ```
 
 ```ini
+# /etc/mysql/my.cnf
 [mysqld]
 innodb_buffer_pool_size        = 3G
 # innodb_buffer_pool_instances   = 4 (default is 1)

diff --git a/07_new-vhost.md b/07_new-vhost.md
@@ -19,6 +19,7 @@ server {
 
         location ~ \.php$ {
                 include snippets/fastcgi-php.conf;
+                # fastcgi_pass unix:/var/run/php/php7.4-fpm.sock;
                 fastcgi_pass unix:/var/run/php/php8.0-fpm.sock;
         }
 

diff --git a/08_setup-ssl.md b/08_setup-ssl.md
@@ -70,10 +70,10 @@ $ sudo nginx -t && sudo systemctl reload nginx
 
 ## Renew Certificates
 
-Configure Certbot to reload NGINX when it successfully renews certificates:
+Configure Certbot to reload NGINX when it successfully renews certificates. Run the following commands:
 
 ```console
-$ echo -e '#!/bin/bash\nnginx -t && systemctl reload nginx' | sudo tee /etc/letsencrypt/renewal-hooks/post/nginx-reload.sh
+$ echo -e '#!/bin/bash\nnginx -t &>/dev/null && systemctl reload nginx' | sudo tee /etc/letsencrypt/renewal-hooks/post/nginx-reload.sh
 $ sudo chmod a+x /etc/letsencrypt/renewal-hooks/post/nginx-reload.sh
 $ sudo nginx -t && sudo systemctl reload nginx
 ```
diff --git a/03_install-lemp.md b/03_install-lemp.md
@@ -34,7 +34,7 @@ mysql> exit
 
 ## Step 3 - Install PHP-FPM
 
-_I've chosen to install PHP 8.0 but you can change any of the commands from `php8.0` to `php8.0` if needed. For example any reference to `php8.0-fpm` can be adjusted simply to `php8.0-fpm`._
+_I've chosen to install PHP 8.0 but you can change any of the commands from `php7.4` to `php8.0` if needed. For example any reference to `php7.4-fpm` can be adjusted simply to `php8.0-fpm`._
 
 ```console
 $ sudo apt-get update

diff --git a/04_configure-php-nginx.md b/04_configure-php-nginx.md
@@ -17,7 +17,7 @@ upload_max_filesize=256M
 date.timezone=Africa/Johannesburg
 [opcache]
 opcache.memory_consumption=256
-opcache.max_accelerated_files=100000
+opcache.max_accelerated_files=50000
 opcache.validate_timestamps=0
 opcache.revalidate_freq=120
 opcache.error_log=/var/log/opcache-errors.log

diff --git a/03_install-lemp.md b/03_install-lemp.md
@@ -34,13 +34,15 @@ mysql> exit
 
 ## Step 3 - Install PHP-FPM
 
+_I've chosen to install PHP 8.0 but you can change any of the commands from `php8.0` to `php8.0` if needed. For example any reference to `php8.0-fpm` can be adjusted simply to `php8.0-fpm`._
+
 ```console
 $ sudo apt-get update
 $ sudo apt -y install lsb-release apt-transport-https ca-certificates wget
 $ wget -O /etc/apt/trusted.gpg.d/php.gpg https://packages.sury.org/php/apt.gpg
 $ echo "deb https://packages.sury.org/php/ $(lsb_release -sc) main" | sudo tee /etc/apt/sources.list.d/php.list
 $ sudo apt update
-$ sudo apt -y install php7.4-{fpm,cli,apc,bcmath,bz2,curl,gd,imagick,intl,memcached,mbstring,mysql,redis,xml,zip}
-$ sudo systemctl start php7.4-fpm
-$ sudo systemctl enable php7.4-fpm
+$ sudo apt -y install php8.0-{fpm,cli,apc,bcmath,bz2,curl,gd,imagick,intl,memcached,mbstring,mysql,redis,xml,zip}
+$ sudo systemctl start php8.0-fpm
+$ sudo systemctl enable php8.0-fpm
 ```
diff --git a/04_configure-php-nginx.md b/04_configure-php-nginx.md
@@ -5,7 +5,7 @@ These are the different configuration files for setting up the servers.
 ## Configure php.ini
 
 ```console
-$ sudo nano /etc/php/7.4/fpm/php.ini
+$ sudo nano /etc/php/8.0/fpm/php.ini
 ```
 
 Change these values:
@@ -54,19 +54,19 @@ apc.lazy_functions=0
 ```
 
 ```console
-$ sudo systemctl reload php7.4-fpm
+$ sudo systemctl reload php8.0-fpm
 ```
 
 ## Configure php-fpm.conf
 
 ```console
-$ sudo nano /etc/php/7.4/fpm/php-fpm.conf
+$ sudo nano /etc/php/8.0/fpm/php-fpm.conf
 ```
 
 ```nginx
-emergency_restart_threshold 10
-emergency_restart_interval 1m
-process_control_timeout 10s
+emergency_restart_threshold=10
+emergency_restart_interval=1m
+process_control_timeout=10s
 ```
 
 ## Configure nginx
@@ -100,7 +100,7 @@ server {
     index index.php index.html index.htm index.nginx-debian.html;
     location ~ \.php$ {
             include snippets/fastcgi-php.conf;
-            fastcgi_pass unix:/run/php/php7.4-fpm.sock;
+            fastcgi_pass unix:/run/php/php8.0-fpm.sock;
     }
 }
 ```

diff --git a/05_fine-tune-php-fpm.md b/05_fine-tune-php-fpm.md
@@ -45,7 +45,7 @@ You're now going to want to download the [ps_mem.py][psmem] file and run the com
 $ cd ~/
 $ wget https://raw.githubusercontent.com/pixelb/ps_mem/master/ps_mem.py
 $ sudo python ps_mem.py | grep php-fpm
-20: 24.8 MiB +   9.0 MiB =  33.7 MiB	php-fpm7.4 (3)
+20: 24.8 MiB +   9.0 MiB =  33.7 MiB	php-fpm8.0 (3)
 ```
 
 **Work It Out**
@@ -69,14 +69,14 @@ The other calculations are now easy because they are all based on how many CPU C
 Change the `www` pool so it now has the following settings. 
 
 ```console
-$ sudo nano /etc/php/7.4/fpm/pool.d/www.conf
+$ sudo nano /etc/php/8.0/fpm/pool.d/www.conf
 ```
 
 ```ini
 [www]
 user = www-data
 group = www-data
-listen = /run/php/php7.4-fpm.sock
+listen = /run/php/php8.0-fpm.sock
 listen.owner = www-data
 listen.group = www-data
 
@@ -99,7 +99,7 @@ pm.max_requests = 500
 Reload PHP:
 
 ```console
-$ sudo systemctl reload php7.4-fpm
+$ sudo systemctl reload php8.0-fpm
 ```
 
 [tuning]: https://tideways.com/profiler/blog/an-introduction-to-php-fpm-tuning

diff --git a/07_new-vhost.md b/07_new-vhost.md
@@ -19,7 +19,7 @@ server {
 
         location ~ \.php$ {
                 include snippets/fastcgi-php.conf;
-                fastcgi_pass unix:/var/run/php/php7.4-fpm.sock;
+                fastcgi_pass unix:/var/run/php/php8.0-fpm.sock;
         }
 
         location ~ /\.ht {

diff --git a/11_install-composer-node-npm.md b/11_install-composer-node-npm.md
@@ -48,6 +48,23 @@ $ npm -v
 6.14.8
 ```
 
+### Install Yarn
+
+With NVM installed you can install `yarn` with the following command:
+
+```console
+$ npm install -g yarn
+```
+
+You can test it out with:
+
+```console
+$ yarn -v
+1.22.10
+```
+
+### Optional
+
 Optionally, you can install the Debian `build-essential` packages as certain node packages require the source code of certain packages when building them at runtime. You probably won't need to do this but I've included it here for those who think they will need it moving forward.
 
 ```composer

diff --git a/03_install-lemp.md b/03_install-lemp.md
@@ -40,7 +40,7 @@ $ sudo apt -y install lsb-release apt-transport-https ca-certificates wget
 $ wget -O /etc/apt/trusted.gpg.d/php.gpg https://packages.sury.org/php/apt.gpg
 $ echo "deb https://packages.sury.org/php/ $(lsb_release -sc) main" | sudo tee /etc/apt/sources.list.d/php.list
 $ sudo apt update
-$ sudo apt -y install php7.4-{fpm,cli,apc,bcmath,bz2,curl,gd,imagick,intl,memcached,mbstring,mysql,xml,zip}
+$ sudo apt -y install php7.4-{fpm,cli,apc,bcmath,bz2,curl,gd,imagick,intl,memcached,mbstring,mysql,redis,xml,zip}
 $ sudo systemctl start php7.4-fpm
 $ sudo systemctl enable php7.4-fpm
 ```
diff --git a/04_configure-php-nginx.md b/04_configure-php-nginx.md
@@ -17,8 +17,9 @@ upload_max_filesize=256M
 date.timezone=Africa/Johannesburg
 [opcache]
 opcache.memory_consumption=256
-opcache.max_accelerated_files=10000
-opcache.validate_timestamps=120
+opcache.max_accelerated_files=100000
+opcache.validate_timestamps=0
+opcache.revalidate_freq=120
 opcache.error_log=/var/log/opcache-errors.log
 [apc]
 apc.shm_size=128M

diff --git a/11_install-composer-node-npm.md b/11_install-composer-node-npm.md
@@ -36,6 +36,7 @@ Debian 10 comes with Node 10 and the following instructions will install Node 12
 $ cd ~
 $ curl -sL https://deb.nodesource.com/setup_12.x -o nodesource_setup.sh
 $ sudo bash nodesource_setup.sh
+$ sudo apt-get install -y nodejs
 ```
 
 Test the installation:

diff --git a/01_introduction.md b/01_introduction.md
@@ -1,13 +1,17 @@
-# How To Install Linux, Nginx, MySQL, PHP on a Debian 10 Virtual Machine
+# How To Install Nginx, MySQL, PHP, Redis and more on a Debian 10 Virtual Machine
 
-This series of documents will configure and setup a Linux, Nginx, MySQL, and 
+This series of documents will configure and setup a Nginx, MySQL, and 
 PHP (LEMP) server on a pretty _feature-rich_ VM running Debian. I used a
 VM with 8GB RAM and 4 CPU Cores so YMML with some of the settings below.
 
+This will also install other useful packages and configurations like,
+Redis, Memcached, Node, NPM, Composer, and a fully automated SSL
+service using certbot for Let's Encrypt.
+
 These documents take you through each step of the configuration from:
 
 1. [General Setup][gen]
-1. [Install Linux, Nginx, MySQL, and PHP][lemp]
+1. [Install Nginx, MySQL, and PHP (LEMP)][lemp]
 1. [Confiure PHP and Nginx][config]
 1. [How to fine-tune PHP-FPM][fpm-tune]
 1. [Fine-tune MySQL/MariaDB for Performance][mysql]

diff --git a/03_install-lemp.md b/03_install-lemp.md
@@ -1,4 +1,4 @@
-# Install Linux, Nginx, MySQL, and PHP
+# Install Nginx, MySQL, and PHP (LEMP)
 
 There are three steps to install the LEMP server and then there are some configuration changes which you need to do.
 

diff --git a/03_install-lemp.md b/03_install-lemp.md
@@ -40,7 +40,7 @@ $ sudo apt -y install lsb-release apt-transport-https ca-certificates wget
 $ wget -O /etc/apt/trusted.gpg.d/php.gpg https://packages.sury.org/php/apt.gpg
 $ echo "deb https://packages.sury.org/php/ $(lsb_release -sc) main" | sudo tee /etc/apt/sources.list.d/php.list
 $ sudo apt update
-$ sudo apt -y install php7.4-{fpm,cli,apc,bcmath,bz2,curl,gd,imagick,intl,mbstring,mysql,xml,zip}
+$ sudo apt -y install php7.4-{fpm,cli,apc,bcmath,bz2,curl,gd,imagick,intl,memcached,mbstring,mysql,xml,zip}
 $ sudo systemctl start php7.4-fpm
 $ sudo systemctl enable php7.4-fpm
 ```
diff --git a/01_introduction.md b/01_introduction.md
@@ -10,12 +10,12 @@ These documents take you through each step of the configuration from:
 1. [Install Linux, Nginx, MySQL, and PHP][lemp]
 1. [Confiure PHP and Nginx][config]
 1. [How to fine-tune PHP-FPM][fpm-tune]
+1. [Fine-tune MySQL/MariaDB for Performance][mysql]
 1. [Create a New Nginx Host][vhost]
 1. [Setup Let's Encrypt SSL certificates][ssl]
 1. [Setup Remote SSH Login with sudo][ssh]
 1. [Install Redis & Memcached Servers][redis]
 1. [Install Composer & Node/NPM][composer]
-1. [Fine-tune MySQL/MariaDB for Performance][mysql]
 
 [gen]: #file-02_general-md
 [lemp]: #file-03_install-lemp-md

diff --git a/0_introduction.md → 01_introduction.md b/0_introduction.md → 01_introduction.md
@@ -17,13 +17,13 @@ These documents take you through each step of the configuration from:
 1. [Install Composer & Node/NPM][composer]
 1. [Fine-tune MySQL/MariaDB for Performance][mysql]
 
-[gen]: #file-1_general-md
-[lemp]: #file-2_install-lemp-md
-[config]: #file-3_configure-php-nginx-md
-[fpm-tune]: #file-4_fine-tune-php-fpm-md
-[mysql]: #file-10_fine-tune-mysql-md
-[vhost]: #file-5_new-vhost-md
-[ssl]: #file-6_setup-ssl-md
-[ssh]: #file-7_ssh-remote-login-md
-[redis]: #file-8_install-redis-memcached-md
-[composer]: #file-9_install-composer-node-npm-md
+[gen]: #file-02_general-md
+[lemp]: #file-03_install-lemp-md
+[config]: #file-04_configure-php-nginx-md
+[fpm-tune]: #file-05_fine-tune-php-fpm-md
+[mysql]: #file-06_fine-tune-mysql-md
+[vhost]: #file-07_new-vhost-md
+[ssl]: #file-08_setup-ssl-md
+[ssh]: #file-09_ssh-remote-login-md
+[redis]: #file-10_install-redis-memcached-md
+[composer]: #file-11_install-composer-node-npm-md
diff --git a/1_general.md → 02_general.md b/1_general.md → 02_general.md
diff --git a/2_install-lemp.md → 03_install-lemp.md b/2_install-lemp.md → 03_install-lemp.md
diff --git a/3_configure-php-nginx.md → 04_configure-php-nginx.md b/3_configure-php-nginx.md → 04_configure-php-nginx.md
diff --git a/4_fine-tune-php-fpm.md → 05_fine-tune-php-fpm.md b/4_fine-tune-php-fpm.md → 05_fine-tune-php-fpm.md
diff --git a/10_fine-tune-mysql.md → 06_fine-tune-mysql.md b/10_fine-tune-mysql.md → 06_fine-tune-mysql.md
diff --git a/5_new-vhost.md → 07_new-vhost.md b/5_new-vhost.md → 07_new-vhost.md
diff --git a/6_setup-ssl.md → 08_setup-ssl.md b/6_setup-ssl.md → 08_setup-ssl.md
diff --git a/7_ssh-remote-login.md → 09_ssh-remote-login.md b/7_ssh-remote-login.md → 09_ssh-remote-login.md
diff --git a/8_install-redis-memcached.md → 10_install-redis-memcached.md b/8_install-redis-memcached.md → 10_install-redis-memcached.md
diff --git a/9_install-composer-node-npm.md → 11_install-composer-node-npm.md b/9_install-composer-node-npm.md → 11_install-composer-node-npm.md
diff --git a/0_introduction.md b/0_introduction.md
@@ -15,11 +15,13 @@ These documents take you through each step of the configuration from:
 1. [Setup Remote SSH Login with sudo][ssh]
 1. [Install Redis & Memcached Servers][redis]
 1. [Install Composer & Node/NPM][composer]
+1. [Fine-tune MySQL/MariaDB for Performance][mysql]
 
 [gen]: #file-1_general-md
 [lemp]: #file-2_install-lemp-md
 [config]: #file-3_configure-php-nginx-md
 [fpm-tune]: #file-4_fine-tune-php-fpm-md
+[mysql]: #file-10_fine-tune-mysql-md
 [vhost]: #file-5_new-vhost-md
 [ssl]: #file-6_setup-ssl-md
 [ssh]: #file-7_ssh-remote-login-md

diff --git a/10_fine-tune-mysql.md b/10_fine-tune-mysql.md
@@ -0,0 +1,77 @@
+# Fine-tune MySQL/MariaDB for Performance
+
+## Increase Open Files Limit
+
+To ensure good server performance, the total number of client connections, database files, and log files must not exceed the maximum file descriptor limit on the operating system `ulimit -n`. Linux systems limit the number of file descriptors that any one process may open to 1,024 per process. On active database servers (especially production ones) it can easily reach the default system limit.
+
+To increase this, edit `/etc/security/limits.conf` and specify or add the following:
+
+```ini
+# Added to increase server limit of 1024 per process.
+mysql            soft    nofile          65535
+mysql            hard    nofile          65535
+```
+
+This requires a system restart. Once rebooted, check the limit with:
+
+```console
+$ ulimit -Sn
+65535
+$ ulimit -Hn
+65535
+```
+
+## Setting Swappiness on Linux for MariaDB
+
+```console
+$ sudo sysctl -w vm.swappiness=1
+$ sudo nano /etc/sysctl.conf
+```
+
+Add this line to the file: `vm.swappiness=1` 
+
+## Filesystem Optimisations for MariaDB
+
+Most database setups do not need to record file access time. You might want to disable this when mounting the volume into the system. To do this, edit your file `/etc/fstab`. For example, on a volume named /dev/sda1, this how it looks like
+
+```config
+/dev/sda1    /    ext4    noatime,errors=remount-ro    0    1
+```
+
+## Tuneup MariaDB To Utilise Memory Efficiently
+
+You have these settings to consideration when fine-tuning your server:
+
+- `innodb_buffer_pool_size`: You can set this from 70-80% of the total available memory on a dedicated database server with only or primarily InnoDB tables. If set to 2 GB or more, you will probably want to adjust `innodb_buffer_pool_instances` as well. You can set this dynamically if you are using MariaDB >= 10.2.2 version.
+- `innodb_flush_log_at_trx_commit`: This setting offers a significant trade-off between performance and reliability. When set to 0, database performance is greatly increased. However, up to 1 second of transactions can be lost in a crash. The default value for this setting is 1.
+- `innodb_flush_method`: Set this to O_DIRECT in order to avoid double buffering data.
+- `innodb_log_file_size`: If you are preferring more performance gains especially during and handling your InnoDB transactions, setting the variable innodb_log_file_size to a larger value such as 5Gib or even 10GiB is reasonable. Increasing means that the larger transactions can run without needing to perform disk I/O before committing. 
+- `max_connections`: If you are application requires a lot of concurrent connections, you can start setting this to 500.
+- `max_allowed_packet`: The max_allowed_packet directive defines the maximum size of packet that can be sent. If the client sends more data than max_allowed_packet size, the socket will be closed. Ideally, especially on most application demands today, you can start setting this to 512M.
+- `back_log`: Increase if you expect short bursts of connections. Cannot be set higher than the operating system limit. To calculate use `(50 + max_connections/5)` to get total value.
+- Query Cache: Preferably you should disable query cache in all of your MariaDB setup. You need to ensure that `query_cache_type=OFF` and `query_cache_size=0` to complete disable query cache. Unlike MySQL, MariaDB is still completely supporting query cache and do not have any plans on withdrawing its support to use query cache.
+- Turn on `slow_query_log` and se the `long_query_time` to 1 second to log queries to `/var/lib/mysql/hostname-slow.log`.
+
+```console
+$ sudo nano /etc/mysql/my.cnf
+```
+
+```ini
+[mysqld]
+innodb_buffer_pool_size        = 3G
+# innodb_buffer_pool_instances   = 4 (default is 1)
+innodb_flush_log_at_trx_commit = 0
+innodb_flush_method            = O_DIRECT
+
+innodb_log_file_size           = 256M
+max_connections                = 500
+# (50 + max_connections/5)
+back_log                       = 150
+max_allowed_packet             = 32M
+# Disable query cache
+query_cache_type               = OFF
+query_cache_size               = 0
+slow_query_log                 = ON
+long_query_time                = 1
+# slow_query_log_file            = /var/lib/mysql/hostname-slow.log
+```
diff --git a/0_introduction.md b/0_introduction.md
@@ -12,16 +12,16 @@ These documents take you through each step of the configuration from:
 1. [How to fine-tune PHP-FPM][fpm-tune]
 1. [Create a New Nginx Host][vhost]
 1. [Setup Let's Encrypt SSL certificates][ssl]
-1. [Setup SFTP server][sftp]
-1. [Install Redis Server][redis]
-1. [Download and Configure phpMyAdmin][pma]
+1. [Setup Remote SSH Login with sudo][ssh]
+1. [Install Redis & Memcached Servers][redis]
+1. [Install Composer & Node/NPM][composer]
 
 [gen]: #file-1_general-md
 [lemp]: #file-2_install-lemp-md
 [config]: #file-3_configure-php-nginx-md
 [fpm-tune]: #file-4_fine-tune-php-fpm-md
 [vhost]: #file-5_new-vhost-md
 [ssl]: #file-6_setup-ssl-md
-[sftp]: #file-7_sftp-setup-md
-[redis]: #file-8_install-redis-md
-[pma]: #file-9_phpmyadmin-md
+[ssh]: #file-7_ssh-remote-login-md
+[redis]: #file-8_install-redis-memcached-md
+[composer]: #file-9_install-composer-node-npm-md
diff --git a/2_install-lemp.md b/2_install-lemp.md
@@ -40,7 +40,7 @@ $ sudo apt -y install lsb-release apt-transport-https ca-certificates wget
 $ wget -O /etc/apt/trusted.gpg.d/php.gpg https://packages.sury.org/php/apt.gpg
 $ echo "deb https://packages.sury.org/php/ $(lsb_release -sc) main" | sudo tee /etc/apt/sources.list.d/php.list
 $ sudo apt update
-$ sudo apt -y install php7.4-{fpm,cli,apc,bcmath,bz2,curl,gd,imagick,intl,mbstring,mysql,zip}
+$ sudo apt -y install php7.4-{fpm,cli,apc,bcmath,bz2,curl,gd,imagick,intl,mbstring,mysql,xml,zip}
 $ sudo systemctl start php7.4-fpm
 $ sudo systemctl enable php7.4-fpm
 ```
diff --git a/7_sftp-setup.md b/7_sftp-setup.md
@@ -1,40 +0,0 @@
-# Setup SFTP server
-
-This uses public/private SSH key for authentication. Your user will only be able to write files in /var/www.
-
-```console
-$ sudo apt-get install openssh-server
-$ sudo addgroup sftp
-$ sudo useradd -m FTPUSER -g sftp
-$ sudo passwd FTPUSER
-$ sudo adduser FTPUSER www-data # add user to group they can write to www folder
-$ sudo chmod -R g+w /var/www # set group write permissions
-$ sudo mkdir -p /home/FTPUSER/.ssh
-$ sudo nano /home/FTPUSER/.ssh/authorized_keys # copy public key from computer and paste here
-$ sudo chmod -R go= /home/FTPUSER/.ssh
-$ sudo chown -R FTPUSER:sftp /home/FTPUSER/.ssh
-$ sudo nano /etc/ssh/sshd_config
-```
-
-```nginx
-PubkeyAuthentication    yes
-Match group sftp
-    X11Forwarding no
-    AllowAgentForwarding no
-    AllowTcpForwarding no
-    ForceCommand internal-sftp
-```
-
-```console
-$ sudo service ssh restart
-```
-
-Test it out using your private key.
-
-```console
-$ sftp -i ~/.ssh/id_rsa [email protected]
-Connected to 140.88.106.229.
-sftp> exit
-```
-
-> **TODO**: figure out why `ChrootDirectory /var/www/` in `/etc/ssh/sshd_config` creates a broken_pipe issue when connecting to the SFTP server. This has been disabled until I can solve this! :scream_cat:

diff --git a/7_ssh-remote-login.md b/7_ssh-remote-login.md
@@ -0,0 +1,57 @@
+# Setup Remote SSH Login with sudo
+
+This uses public/private SSH key for authentication.
+
+```console
+$ sudo apt-get install openssh-server
+$ sudo useradd -m USERNAME -g www-data # add user to group they can write to www folder
+$ sudo passwd USERNAME # set password for login
+$ sudo chmod -R g+w /var/www # set group write permissions
+$ sudo mkdir -p /home/USERNAME/.ssh
+$ sudo nano /home/USERNAME/.ssh/authorized_keys # copy your `~/.ssh/id_rsa.pub` key from computer and paste here
+$ sudo chmod -R go= /home/USERNAME/.ssh
+$ sudo chown -R USERNAME:www-data /home/USERNAME
+$ sudo usermod -a -G sudo USERNAME # optionally, add user to sudoers file
+$ sudo service ssh restart
+```
+
+Now login to the SSH server with your private key and test:
+
+```console
+$ ssh -i ~/.ssh/id_rsa [email protected]
+Linux server.com 4.19.0-13-amd64 #1 SMP Debian 4.19.160-2 (2020-11-28) x86_64
+
+The programs included with the Debian GNU/Linux system are free software;
+the exact distribution terms for each program are described in the
+individual files in /usr/share/doc/*/copyright.
+
+Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
+permitted by applicable law.
+Last login: Tue Dec  8 23:12:02 2020 from 104.245.101.122
+USERNAME@server:~#
+```
+
+If all goes well you won't be prompted for a password and you will just login straight away. If you are asked for a password you have done something wrong. Try again.
+
+## Turn off sudo password authentication
+
+With the above configured you will still be prompted for your password when running a `sudo` command on the server. To disable the prompting of passwords, do the following.
+
+```console
+$ sudo visudo
+```
+
+Add your username to the end of the file so it looks similar to:
+
+```bash
+# Allow members of group sudo to execute any command
+%sudo   ALL=(ALL:ALL) ALL
+#includedir /etc/sudoers.d
+USERNAME  ALL=(ALL) NOPASSWD: ALL
+```
+
+**NB:** replace `USERNAME` with the username you created, don't leave it as is. Then save the file and restart the `ssh` server.
+
+```console
+$ sudo service ssh restart
+```
diff --git a/8_install-redis-memcached.md b/8_install-redis-memcached.md
@@ -0,0 +1,57 @@
+# Install and Setup Redis & Memcached Servers
+
+## Install Redis
+
+```console
+$ sudo apt install redis-server
+```
+
+### Edit Configuration
+
+```console
+$ sudo nano /etc/redis/redis.conf
+```
+
+Change these settings:
+
+```ini
+supervised systemd # use Debian's systemd
+bind 127.0.0.1 ::1
+# If you want to secure your Redis server set a password below.
+# requirepass change-this-password
+```
+
+### Restart Redis
+
+```console
+$ sudo systemctl restart redis
+$ sudo systemctl status redis
+```
+
+## Install Memcached
+
+```console
+$ sudo apt install memcached libmemcached-tools
+$ sudo systemctl status memcached
+```
+
+### Edit Configuration
+
+```console
+$ sudo nano /etc/memcached.conf
+```
+
+Change at least this setting:
+
+```ini
+# Start with a cap of 64 megs of memory. It's reasonable, and the daemon default
+# Note that the daemon will grow to this size, but does not start out holding this much
+# memory
+-m 256
+```
+
+### Restart Memcached
+
+```console
+$ sudo systemctl restart memcached
+```
diff --git a/8_install-redis.md b/8_install-redis.md
@@ -1,29 +0,0 @@
-# Install and Setup Redis Server
-
-## Install Redis
-
-```console
-$ sudo apt install redis-server
-```
-
-## Edit Configuration
-
-```console
-$ sudo nano /etc/redis/redis.conf
-```
-
-Change these settings:
-
-```ini
-supervised systemd # use Debian's systemd
-bind 127.0.0.1 ::1
-# If you want to secure your Redis server set a password below.
-# requirepass change-this-password
-```
-
-## Restart Redis
-
-```console
-$ sudo systemctl restart redis
-$ sudo systemctl status redis
-```

diff --git a/9_install-composer-node-npm.md b/9_install-composer-node-npm.md
@@ -0,0 +1,57 @@
+# Installing Composer and Node/NPM
+
+This section covers the instructions to installing [Composer][compser] and [Node.js and NPM][node] on your server.
+
+## Install Composer
+
+```console
+$ sudo apt install curl git unzip zip
+$ cd ~
+$ php -r "copy('https://getcomposer.org/installer', 'composer-setup.php');"
+$ php -r "if (hash_file('sha384', 'composer-setup.php') === '756890a4488ce9024fc62c56153228907f1545c228516cbf63f885e036d37e9a59d27d63f46af1d4d07ee0f76181c7d3') { echo 'Installer verified'; } else { echo 'Installer corrupt'; unlink('composer-setup.php'); } echo PHP_EOL;"
+$ sudo php composer-setup.php --install-dir=/usr/local/bin --filename=composer
+$ php -r "unlink('composer-setup.php');"
+```
+
+Composer will be installed at `/usr/local/bin/composer` and you can test the installation as follows:
+
+```console
+$ /usr/local/bin/composer -v
+   ______
+  / ____/___  ____ ___  ____  ____  ________  _____
+ / /   / __ \/ __ `__ \/ __ \/ __ \/ ___/ _ \/ ___/
+/ /___/ /_/ / / / / / / /_/ / /_/ (__  )  __/ /
+\____/\____/_/ /_/ /_/ .___/\____/____/\___/_/
+                    /_/
+Composer version 2.0.8 2020-12-03 17:20:38
+```
+
+If you get an error output stating `Installer corrupt`, it means the version of composer has been updated and you'll need a new hash. Visit the official [getcomposer.org download page][compser] to get the latest `hash_file` string and/or install via that method.
+
+## Install Node & NPM
+
+Debian 10 comes with Node 10 and the following instructions will install Node 12 and NPM 6 by installing from source. If you would like to install Node 14 simply replace `setup_12.x` in the command below with `setup_14.x`. If that's not high enough and you'd like Node 15, replace the command with `setup_15.x` instead.
+
+```console
+$ cd ~
+$ curl -sL https://deb.nodesource.com/setup_12.x -o nodesource_setup.sh
+$ sudo bash nodesource_setup.sh
+```
+
+Test the installation:
+
+```console
+$ node -v
+v12.20.0
+$ npm -v
+6.14.8
+```
+
+Optionally, you can install the Debian `build-essential` packages as certain node packages require the source code of certain packages when building them at runtime. You probably won't need to do this but I've included it here for those who think they will need it moving forward.
+
+```composer
+$ sudo apt install build-essential
+```
+
+[compser]: https://getcomposer.org/download/
+[node]: https://nodejs.org/
diff --git a/9_phpmyadmin.md b/9_phpmyadmin.md
@@ -1,70 +0,0 @@
-# Download and Configure phpMyAdmin
-
-```console
-$ cd /var/www/html
-$ sudo -u www-data mkdir phpmyadmin
-$ sudo -u www-data wget https://files.phpmyadmin.net/phpMyAdmin/5.0.4/phpMyAdmin-5.0.4-english.tar.gz
-$ sudo -u www-data tar -zxf phpMyAdmin-5.0.4-english.tar.gz -C phpmyadmin --strip-components 1
-$ sudo -u www-data rm phpMyAdmin-5.0.4-english.tar.gz
-```
-
-1. Open phpMyAdmin in a browser and log in as root.
-1. Create a database called `phpmyadmin`
-1. Create a user called `pma` and set the *host* to `localhost`.
-1. Open the SQL dump file in `/var/www/html/phpmyadmin/create_tables.sql`.
-1. In phpMyAdmin, select the `phpmyadmin` database and click on the *SQL* tab.
-1. Copy/paste the entire text from `create_tables.sql` into the text box, and run the query.
-1. Open the `config.inc.php` file in the phpMyAdmin install directory, and add the following.
-
-```php
-/* Blowfish needed for cookie based authentication. MUST to be 32 chars long. */
-$cfg['blowfish_secret'] = '12345678901234567890123456789012';
-$cfg['DefaultConnectionCollation'] = 'utf8mb4_unicode_ci';
-/* Servers configuration */
-$i = 0;
-/* First server */
-$i++;
-/* Authentication type */
-$cfg['Servers'][$i]['auth_type'] = 'cookie';
-/* Server parameters */
-$cfg['Servers'][$i]['host'] = 'localhost';
-$cfg['Servers'][$i]['compress'] = false;
-$cfg['Servers'][$i]['AllowNoPassword'] = false;
-/* Hide system dbs */
-$cfg['Servers'][$i]['hide_db'] = '^(information_schema|mysql|performance_schema|sys)$';
-/* phpMyAdmin configuration storage settings. */
-$cfg['Servers'][$i]['controluser'] = 'phpmyadmin';
-$cfg['Servers'][$i]['controlpass'] = 'ADD_DB_PASSWORD';
-/* phpMyAdmin storage database and tables */
-$cfg['Servers'][$i]['pmadb'] = 'phpmyadmin';
-$cfg['Servers'][$i]['bookmarktable'] = 'pma__bookmark';
-$cfg['Servers'][$i]['relation'] = 'pma__relation';
-$cfg['Servers'][$i]['table_info'] = 'pma__table_info';
-$cfg['Servers'][$i]['table_coords'] = 'pma__table_coords';
-$cfg['Servers'][$i]['pdf_pages'] = 'pma__pdf_pages';
-$cfg['Servers'][$i]['column_info'] = 'pma__column_info';
-$cfg['Servers'][$i]['history'] = 'pma__history';
-$cfg['Servers'][$i]['table_uiprefs'] = 'pma__table_uiprefs';
-$cfg['Servers'][$i]['tracking'] = 'pma__tracking';
-$cfg['Servers'][$i]['userconfig'] = 'pma__userconfig';
-$cfg['Servers'][$i]['recent'] = 'pma__recent';
-$cfg['Servers'][$i]['favorite'] = 'pma__favorite';
-$cfg['Servers'][$i]['users'] = 'pma__users';
-$cfg['Servers'][$i]['usergroups'] = 'pma__usergroups';
-$cfg['Servers'][$i]['navigationhiding'] = 'pma__navigationhiding';
-$cfg['Servers'][$i]['savedsearches'] = 'pma__savedsearches';
-$cfg['Servers'][$i]['central_columns'] = 'pma__central_columns';
-$cfg['Servers'][$i]['designer_settings'] = 'pma__designer_settings';
-$cfg['Servers'][$i]['export_templates'] = 'pma__export_templates';
-/* Directories for saving/loading files from server */
-$cfg['UploadDir'] = '';
-$cfg['SaveDir'] = '';
-/* General config */
-$cfg['RowActionType'] = 'icons';
-$cfg['ShowAll'] = true;
-$cfg['MaxRows'] = 50;
-$cfg['QueryHistoryDB'] = true;
-$cfg['QueryHistoryMax'] = 100;
-$cfg['SendErrorReports'] = 'never';
-$cfg['Console']['DarkTheme'] = true;
-```

diff --git a/4_fine-tune-php-fpm.md b/4_fine-tune-php-fpm.md
@@ -1,6 +1,6 @@
 # How to fine-tune PHP-FPM
 
-This section outlines how to go about configuring your php-fpm `www.conf` pool file. It may seem complicated and overwhelming and you can totally skip this if you want to. That said, overlooking this step is like buying a sports car and never going above 20 mph; you're going to kill the engine by not using the car correctly. You really do want to maximise your server as much as possible to avoid bottlenecks and crashes.
+This section outlines how to go about configuring your php-fpm `www.conf` pool file. It may seem complicated and overwhelming and you can totally skip this if you want to. That said, overlooking this step is like buying a sports car and never going above 20 mph; you're going to kill the engine by not using the car correctly. You really do want to maximise your server as much as possible to avoid bottlenecks and crashes later on.
 
 ## An Overview
 
@@ -21,11 +21,11 @@ Here are the settings and calculations. The `Value` column has details on how to
 
 ### How to calculate max_children
 
-Let's assume, for this example, you have a server with **8GB RAM** and **4 CPU Cores**. With this in mind we can now continue to work this formula out:
+Let's assume, for this example, you have a server with **8GB RAM** and **4 CPU Cores**. With this in mind we can continue to work this formula out:
 
 `(Total RAM - Memory used on server) / Process Size = max_children`
 
-First let's run some commands on the server to get the data we need for the calculation.
+First let's run some commands on the server to get the data we need for the formula.
 
 **Memory Usage**
 
@@ -50,13 +50,13 @@ $ sudo python ps_mem.py | grep php-fpm
 
 **Work It Out**
 
-We've not got everything we need so now we can apply this info to the calculation as follows.
+We've got everything we need to apply these values to the formula as follows:
 
-- `Total RAM` = `7800` (for 7.8GB) this is the `total` column value when running `sudo free -hl`
-- `Memory Used` = `331` this is the `used` column value when running `sudo free -hl`
-- `Process Size` = `33.7` which is the total after running `sudo python ps_mem.py | grep php-fpm`
+- `Total RAM` = `7800` is the `total` column value (`7.8Gi`) when running `sudo free -hl`
+- `Memory Used` = `331` is the `used` column value (`331Mi`) when running `sudo free -hl`
+- `Process Size` = `33.7` is the total value (`33.7 MiB`) after executing `sudo python ps_mem.py | grep php-fpm`
 
-Now you pull this all together and run the formula of `(Total RAM - Memory used on server) / Process Size` it will give you something like this:
+Pull this all together and run the formula of `(Total RAM - Memory used on server) / Process Size` which will give you something similar to this:
 
 > **(7800 - 331) / 33.7 = 221.63**
 
@@ -86,7 +86,7 @@ listen.group = www-data
 pm = dynamic
 ; (Mem - Used) / ps_mem.py = max_children
 ; (7800 - 331) / 33.7      = 221.63
-pm.max_children = 220
+pm.max_children = 222
 ; CPU * 4 = 16
 pm.start_servers = 16
 ; CPU * 2 = 8

diff --git a/4_fine-tune-php-fpm.md b/4_fine-tune-php-fpm.md
@@ -21,14 +21,16 @@ Here are the settings and calculations. The `Value` column has details on how to
 
 ### How to calculate max_children
 
-If you have a server with **8GB RAM** and **4 CPU Cores** this is how you work this formula out:
+Let's assume, for this example, you have a server with **8GB RAM** and **4 CPU Cores**. With this in mind we can now continue to work this formula out:
 
 `(Total RAM - Memory used on server) / Process Size = max_children`
 
-First let's run some commands on the server to get the data we need.
+First let's run some commands on the server to get the data we need for the calculation.
 
 **Memory Usage**
 
+We need to know how much `total` memory we have as well as how much of the memory is `used`. The rest is irrelevant.
+
 ```console
 $ sudo free -hl
               total        used        free      shared  buff/cache   available
@@ -37,6 +39,8 @@ Mem:          7.8Gi       331Mi       6.0Gi        27Mi       1.5Gi       7.1Gi
 
 **Process Memory**
 
+You're now going to want to download the [ps_mem.py][psmem] file and run the command. When done we are only interested in the total amount the sum calculates; i.e. the total amount in `MiB` after the `=` sign.
+
 ```console
 $ cd ~/
 $ wget https://raw.githubusercontent.com/pixelb/ps_mem/master/ps_mem.py
@@ -46,6 +50,8 @@ $ sudo python ps_mem.py | grep php-fpm
 
 **Work It Out**
 
+We've not got everything we need so now we can apply this info to the calculation as follows.
+
 - `Total RAM` = `7800` (for 7.8GB) this is the `total` column value when running `sudo free -hl`
 - `Memory Used` = `331` this is the `used` column value when running `sudo free -hl`
 - `Process Size` = `33.7` which is the total after running `sudo python ps_mem.py | grep php-fpm`

diff --git a/4_fine-tune-php-fpm.md b/4_fine-tune-php-fpm.md
@@ -1,12 +1,12 @@
 # How to fine-tune PHP-FPM
 
-This section outlines how to go about configuring your php-fpm `www.conf` pool file.
+This section outlines how to go about configuring your php-fpm `www.conf` pool file. It may seem complicated and overwhelming and you can totally skip this if you want to. That said, overlooking this step is like buying a sports car and never going above 20 mph; you're going to kill the engine by not using the car correctly. You really do want to maximise your server as much as possible to avoid bottlenecks and crashes.
 
 ## An Overview
 
-You are probably going to want to read [this article on FPM tuning][tuning] which I used to determine the settings below. The article will help you scientifically calculate the exact setting you should use for `max_children`, `start_servers`, `min_spare_servers`, and `max_spare_servers`. The most complicated one to calculate is `max_children` because there is a formula he uses to do this which is `(Total RAM - Memory used on server) / Process Size = max_children`. I've tried my best to give you the succinct version of what to calculate, as well as how, but depending on your level of skill, you may need to read the article fully.
+You are probably going to want to read [this article on FPM tuning][tuning] which I used to determine the settings below. The article will help you scientifically calculate the exact settings you should use for `max_children`, `start_servers`, `min_spare_servers`, and `max_spare_servers`. The most complicated one to calculate is `max_children` because there is a formula he uses to do this which is `(Total RAM - Memory used on server) / Process Size = max_children`. I've tried my best to give you the succinct version of what to calculate, as well as how, but depending on your level of skill, you may need to read the article fully.
 
-There is also reference to a script called `ps_mem.py` which you can [download directly from here][psmem], or you can run `wget https://raw.githubusercontent.com/pixelb/ps_mem/master/ps_mem.py` from your server to download the file there instead. This script will give you the total `Process Size` needed in the `max_children` formula above and is an amazing tool for helping you determine your resources available.
+There is also reference to a script called [`ps_mem.py`][psmem] which, when run on your server, will give you the total `Process Size` needed in the `max_children` formula above.
 
 ## Calculations
 
@@ -21,19 +21,40 @@ Here are the settings and calculations. The `Value` column has details on how to
 
 ### How to calculate max_children
 
-If you have a server with **8GB RAM** and **4 CPU Cores** this is how you work this out.
+If you have a server with **8GB RAM** and **4 CPU Cores** this is how you work this formula out:
 
 `(Total RAM - Memory used on server) / Process Size = max_children`
 
-- `Total RAM` = `7800` (for 7.8GB) run `sudo free -hl` from the command line to get this
-- `Memory Used` = Run `sudo free -hl` from the command line to get the total used memory (e.g. 331MB)
-- `Process Size` = Run the [ps_mem.py][psmem] script by executing `sudo python ps_mem.py | grep php-fpm`. This would output something similar to this `24.8 MiB + 9.0 MiB = 33.7 MiB`. The value of `Process Size` is therefor `33.7`.
+First let's run some commands on the server to get the data we need.
+
+**Memory Usage**
+
+```console
+$ sudo free -hl
+              total        used        free      shared  buff/cache   available
+Mem:          7.8Gi       331Mi       6.0Gi        27Mi       1.5Gi       7.1Gi
+```
+
+**Process Memory**
+
+```console
+$ cd ~/
+$ wget https://raw.githubusercontent.com/pixelb/ps_mem/master/ps_mem.py
+$ sudo python ps_mem.py | grep php-fpm
+20: 24.8 MiB +   9.0 MiB =  33.7 MiB	php-fpm7.4 (3)
+```
+
+**Work It Out**
+
+- `Total RAM` = `7800` (for 7.8GB) this is the `total` column value when running `sudo free -hl`
+- `Memory Used` = `331` this is the `used` column value when running `sudo free -hl`
+- `Process Size` = `33.7` which is the total after running `sudo python ps_mem.py | grep php-fpm`
 
 Now you pull this all together and run the formula of `(Total RAM - Memory used on server) / Process Size` it will give you something like this:
 
 > **(7800 - 331) / 33.7 = 221.63**
 
-Therefore: `max_children = 222`
+Therefore, we now know that `max_children = 222` 👍🏿 
 
 The other calculations are now easy because they are all based on how many CPU Cores your have. Open up the `www.conf` file and begin editing with your newly calculated values.
 
@@ -69,6 +90,8 @@ pm.max_spare_servers = 16
 pm.max_requests = 500
 ```
 
+Reload PHP:
+
 ```console
 $ sudo systemctl reload php7.4-fpm
 ```

diff --git a/3_configure-php-nginx.md b/3_configure-php-nginx.md
@@ -112,6 +112,3 @@ nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
 nginx: configuration file /etc/nginx/nginx.conf test is successful
 $ sudo systemctl reload nginx
 ```
-
-[tuning]: https://tideways.com/profiler/blog/an-introduction-to-php-fpm-tuning
-[psmem]: https://raw.githubusercontent.com/pixelb/ps_mem/master/ps_mem.py
diff --git a/4_fine-tune-php-fpm.md b/4_fine-tune-php-fpm.md
@@ -71,4 +71,7 @@ pm.max_requests = 500
 
 ```console
 $ sudo systemctl reload php7.4-fpm
-```
+```
+
+[tuning]: https://tideways.com/profiler/blog/an-introduction-to-php-fpm-tuning
+[psmem]: https://raw.githubusercontent.com/pixelb/ps_mem/master/ps_mem.py
diff --git a/0_introduction.md b/0_introduction.md
@@ -9,7 +9,8 @@ These documents take you through each step of the configuration from:
 1. [General Setup][gen]
 1. [Install Linux, Nginx, MySQL, and PHP][lemp]
 1. [Confiure PHP and Nginx][config]
-1. [Create a new nginx vhost][vhost]
+1. [How to fine-tune PHP-FPM][fpm-tune]
+1. [Create a New Nginx Host][vhost]
 1. [Setup Let's Encrypt SSL certificates][ssl]
 1. [Setup SFTP server][sftp]
 1. [Install Redis Server][redis]
@@ -18,8 +19,9 @@ These documents take you through each step of the configuration from:
 [gen]: #file-1_general-md
 [lemp]: #file-2_install-lemp-md
 [config]: #file-3_configure-php-nginx-md
-[vhost]: #file-4_new-vhost-md
-[ssl]: #file-5_setup-ssl-md
-[sftp]: #file-6_sftp-setup-md
-[redis]: #file-7_install-redis-md
-[pma]: #file-8_phpmyadmin-md
+[fpm-tune]: #file-4_fine-tune-php-fpm-md
+[vhost]: #file-5_new-vhost-md
+[ssl]: #file-6_setup-ssl-md
+[sftp]: #file-7_sftp-setup-md
+[redis]: #file-8_install-redis-md
+[pma]: #file-9_phpmyadmin-md
diff --git a/3_configure-php-nginx.md b/3_configure-php-nginx.md
@@ -68,79 +68,6 @@ emergency_restart_interval 1m
 process_control_timeout 10s
 ```
 
-## Configure php-fpm www.conf
-
-### An Overview
-
-You are probably going to want to read [this article on FPM tuning][tuning] which I used to determine the settings below. The article will help you scientifically calculate the exact setting you should use for `max_children`, `start_servers`, `min_spare_servers`, and `max_spare_servers`. The most complicated one to calculate is `max_children` because there is a formula he uses to do this which is `(Total RAM - Memory used on server) / Process Size = max_children`. I've tried my best to give you the succinct version of what to calculate, as well as how, but depending on your level of skill, you may need to read the article fully.
-
-There is also reference to a script called `ps_mem.py` which you can [download directly from here][psmem], or you can run `wget https://raw.githubusercontent.com/pixelb/ps_mem/master/ps_mem.py` from your server to download the file there instead. This script will give you the total `Process Size` needed in the `max_children` formula above and is an amazing tool for helping you determine your resources available.
-
-### Calculations
-
-Here are the settings and calculations. The `Value` column has details on how to calculate the `Setting` value.
-
-| Setting              | Value                                                    |
-|:---------------------|:---------------------------------------------------------|
-| `max_children`       | (`Total RAM` - `Memory` used on server) / `Process Size` |
-| `start_servers`      | Number of CPU cores x 4                                  |
-| `min_spare_servers`  | Number of CPU cores x 2                                  |
-| `max_spare_servers`  | Equal to same value as `start_servers`                   |
-
-#### How to calculate max_children
-
-If you have a server with **8GB RAM** and **4 CPU Cores** this is how you work this out.
-
-`(Total RAM - Memory used on server) / Process Size = max_children`
-
-- `Total RAM` = `7800` (for 7.8GB) run `sudo free -hl` from the command line to get this
-- `Memory Used` = Run `sudo free -hl` from the command line to get the total used memory (e.g. 331MB)
-- `Process Size` = Run the [ps_mem.py][psmem] script by executing `sudo python ps_mem.py | grep php-fpm`. This would output something similar to this `24.8 MiB + 9.0 MiB = 33.7 MiB`. The value of `Process Size` is therefor `33.7`.
-
-Now you pull this all together and run the formula of `(Total RAM - Memory used on server) / Process Size` it will give you something like this:
-
-> **(7800 - 331) / 33.7 = 221.63**
-
-Therefore: `max_children = 222`
-
-The other calculations are now easy because they are all based on how many CPU Cores your have. Open up the `www.conf` file and begin editing with your newly calculated values.
-
-### Edit the Settings
-
-Change the `www` pool so it now has the following settings. 
-
-```console
-$ sudo nano /etc/php/7.4/fpm/pool.d/www.conf
-```
-
-```ini
-[www]
-user = www-data
-group = www-data
-listen = /run/php/php7.4-fpm.sock
-listen.owner = www-data
-listen.group = www-data
-
-; Server Resources: 8G RAM | 4x CPU Cores
-; `free -hl` output: Total 7.8Gi   Used 331Mi    Free 5.8Gi
-; `ps_mem.py` output: 24.8 MiB + 9.0 MiB = 33.7 MiB
-pm = dynamic
-; (Mem - Used) / ps_mem.py = max_children
-; (7800 - 331) / 33.7      = 221.63
-pm.max_children = 220
-; CPU * 4 = 16
-pm.start_servers = 16
-; CPU * 2 = 8
-pm.min_spare_servers = 8
-; Same as children
-pm.max_spare_servers = 16
-pm.max_requests = 500
-```
-
-```console
-$ sudo systemctl reload php7.4-fpm
-```
-
 ## Configure nginx
 
 ```console

diff --git a/4_fine-tune-php-fpm.md b/4_fine-tune-php-fpm.md
@@ -0,0 +1,74 @@
+# How to fine-tune PHP-FPM
+
+This section outlines how to go about configuring your php-fpm `www.conf` pool file.
+
+## An Overview
+
+You are probably going to want to read [this article on FPM tuning][tuning] which I used to determine the settings below. The article will help you scientifically calculate the exact setting you should use for `max_children`, `start_servers`, `min_spare_servers`, and `max_spare_servers`. The most complicated one to calculate is `max_children` because there is a formula he uses to do this which is `(Total RAM - Memory used on server) / Process Size = max_children`. I've tried my best to give you the succinct version of what to calculate, as well as how, but depending on your level of skill, you may need to read the article fully.
+
+There is also reference to a script called `ps_mem.py` which you can [download directly from here][psmem], or you can run `wget https://raw.githubusercontent.com/pixelb/ps_mem/master/ps_mem.py` from your server to download the file there instead. This script will give you the total `Process Size` needed in the `max_children` formula above and is an amazing tool for helping you determine your resources available.
+
+## Calculations
+
+Here are the settings and calculations. The `Value` column has details on how to calculate the `Setting` value.
+
+| Setting              | Value                                                    |
+|:---------------------|:---------------------------------------------------------|
+| `max_children`       | (`Total RAM` - `Memory` used on server) / `Process Size` |
+| `start_servers`      | Number of CPU cores x 4                                  |
+| `min_spare_servers`  | Number of CPU cores x 2                                  |
+| `max_spare_servers`  | Equal to same value as `start_servers`                   |
+
+### How to calculate max_children
+
+If you have a server with **8GB RAM** and **4 CPU Cores** this is how you work this out.
+
+`(Total RAM - Memory used on server) / Process Size = max_children`
+
+- `Total RAM` = `7800` (for 7.8GB) run `sudo free -hl` from the command line to get this
+- `Memory Used` = Run `sudo free -hl` from the command line to get the total used memory (e.g. 331MB)
+- `Process Size` = Run the [ps_mem.py][psmem] script by executing `sudo python ps_mem.py | grep php-fpm`. This would output something similar to this `24.8 MiB + 9.0 MiB = 33.7 MiB`. The value of `Process Size` is therefor `33.7`.
+
+Now you pull this all together and run the formula of `(Total RAM - Memory used on server) / Process Size` it will give you something like this:
+
+> **(7800 - 331) / 33.7 = 221.63**
+
+Therefore: `max_children = 222`
+
+The other calculations are now easy because they are all based on how many CPU Cores your have. Open up the `www.conf` file and begin editing with your newly calculated values.
+
+## Edit the Settings
+
+Change the `www` pool so it now has the following settings. 
+
+```console
+$ sudo nano /etc/php/7.4/fpm/pool.d/www.conf
+```
+
+```ini
+[www]
+user = www-data
+group = www-data
+listen = /run/php/php7.4-fpm.sock
+listen.owner = www-data
+listen.group = www-data
+
+; Server Resources: 8G RAM | 4x CPU Cores
+; `free -hl` output: Total 7.8Gi   Used 331Mi    Free 5.8Gi
+; `ps_mem.py` output: 24.8 MiB + 9.0 MiB = 33.7 MiB
+pm = dynamic
+; (Mem - Used) / ps_mem.py = max_children
+; (7800 - 331) / 33.7      = 221.63
+pm.max_children = 220
+; CPU * 4 = 16
+pm.start_servers = 16
+; CPU * 2 = 8
+pm.min_spare_servers = 8
+; Same as children
+pm.max_spare_servers = 16
+pm.max_requests = 500
+```
+
+```console
+$ sudo systemctl reload php7.4-fpm
+```
diff --git a/4_new-vhost.md → 5_new-vhost.md b/4_new-vhost.md → 5_new-vhost.md
@@ -1,4 +1,6 @@
-# Create a new nginx vhost
+# Create a New Nginx Host
+
+It's time to setup your domain on nginx and this is how you go about enabling it and ensuring PHP-FPM is working for the host.
 
 ```console
 $ sudo nano /etc/nginx/sites-available/example.com

diff --git a/5_setup-ssl.md → 6_setup-ssl.md b/5_setup-ssl.md → 6_setup-ssl.md
diff --git a/6_sftp-setup.md → 7_sftp-setup.md b/6_sftp-setup.md → 7_sftp-setup.md
diff --git a/7_install-redis.md → 8_install-redis.md b/7_install-redis.md → 8_install-redis.md
diff --git a/8_phpmyadmin.md → 9_phpmyadmin.md b/8_phpmyadmin.md → 9_phpmyadmin.md
diff --git a/3_configure-php-nginx.md b/3_configure-php-nginx.md
@@ -72,9 +72,9 @@ process_control_timeout 10s
 
 ### An Overview
 
-You are probably going to want to read [this article on FPM tuning][tuning] which I used to determine the settings below. The article will help you scientifically calculate the exact setting you should use for `max_children`, `start_servers`, `min_spare_servers`, and `max_spare_servers`. The most complicated one to calculate is `max_children` because there is a formula he uses to do this which is `(Total RAM - Memory used on server) / Process Size = max_children`. I've tried my best to give you the succinct version of what to calculate and how but depending on your level of skill you may need to read the article fully.
+You are probably going to want to read [this article on FPM tuning][tuning] which I used to determine the settings below. The article will help you scientifically calculate the exact setting you should use for `max_children`, `start_servers`, `min_spare_servers`, and `max_spare_servers`. The most complicated one to calculate is `max_children` because there is a formula he uses to do this which is `(Total RAM - Memory used on server) / Process Size = max_children`. I've tried my best to give you the succinct version of what to calculate, as well as how, but depending on your level of skill, you may need to read the article fully.
 
-There is also reference to a script called `ps_mem.py` which you can [download directly from here][psmem]. This script will give you the total `Process Size` needed in the `max_children` formula above.
+There is also reference to a script called `ps_mem.py` which you can [download directly from here][psmem], or you can run `wget https://raw.githubusercontent.com/pixelb/ps_mem/master/ps_mem.py` from your server to download the file there instead. This script will give you the total `Process Size` needed in the `max_children` formula above and is an amazing tool for helping you determine your resources available.
 
 ### Calculations
 

diff --git a/0_introduction.md b/0_introduction.md
@@ -1,4 +1,4 @@
-# How To Install Linux, Nginx, MySQL, PHP on an Ubuntu Azure Virtual Machine
+# How To Install Linux, Nginx, MySQL, PHP on a Debian 10 Virtual Machine
 
 This series of documents will configure and setup a Linux, Nginx, MySQL, and 
 PHP (LEMP) server on a pretty _feature-rich_ VM running Debian. I used a

diff --git a/2_install-lemp.md b/2_install-lemp.md
@@ -4,7 +4,7 @@ There are three steps to install the LEMP server and then there are some configu
 
 ## Step 1 - Install Nginx
 
-```
+```console
 $ sudo apt update
 $ sudo apt install nginx
 $ sudo systemctl start nginx

diff --git a/3_configure-php-nginx.md b/3_configure-php-nginx.md
@@ -62,20 +62,57 @@ $ sudo systemctl reload php7.4-fpm
 $ sudo nano /etc/php/7.4/fpm/php-fpm.conf
 ```
 
-```ini
+```nginx
 emergency_restart_threshold 10
 emergency_restart_interval 1m
 process_control_timeout 10s
 ```
 
 ## Configure php-fpm www.conf
 
+### An Overview
+
+You are probably going to want to read [this article on FPM tuning][tuning] which I used to determine the settings below. The article will help you scientifically calculate the exact setting you should use for `max_children`, `start_servers`, `min_spare_servers`, and `max_spare_servers`. The most complicated one to calculate is `max_children` because there is a formula he uses to do this which is `(Total RAM - Memory used on server) / Process Size = max_children`. I've tried my best to give you the succinct version of what to calculate and how but depending on your level of skill you may need to read the article fully.
+
+There is also reference to a script called `ps_mem.py` which you can [download directly from here][psmem]. This script will give you the total `Process Size` needed in the `max_children` formula above.
+
+### Calculations
+
+Here are the settings and calculations. The `Value` column has details on how to calculate the `Setting` value.
+
+| Setting              | Value                                                    |
+|:---------------------|:---------------------------------------------------------|
+| `max_children`       | (`Total RAM` - `Memory` used on server) / `Process Size` |
+| `start_servers`      | Number of CPU cores x 4                                  |
+| `min_spare_servers`  | Number of CPU cores x 2                                  |
+| `max_spare_servers`  | Equal to same value as `start_servers`                   |
+
+#### How to calculate max_children
+
+If you have a server with **8GB RAM** and **4 CPU Cores** this is how you work this out.
+
+`(Total RAM - Memory used on server) / Process Size = max_children`
+
+- `Total RAM` = `7800` (for 7.8GB) run `sudo free -hl` from the command line to get this
+- `Memory Used` = Run `sudo free -hl` from the command line to get the total used memory (e.g. 331MB)
+- `Process Size` = Run the [ps_mem.py][psmem] script by executing `sudo python ps_mem.py | grep php-fpm`. This would output something similar to this `24.8 MiB + 9.0 MiB = 33.7 MiB`. The value of `Process Size` is therefor `33.7`.
+
+Now you pull this all together and run the formula of `(Total RAM - Memory used on server) / Process Size` it will give you something like this:
+
+> **(7800 - 331) / 33.7 = 221.63**
+
+Therefore: `max_children = 222`
+
+The other calculations are now easy because they are all based on how many CPU Cores your have. Open up the `www.conf` file and begin editing with your newly calculated values.
+
+### Edit the Settings
+
+Change the `www` pool so it now has the following settings. 
+
 ```console
 $ sudo nano /etc/php/7.4/fpm/pool.d/www.conf
 ```
 
-Change so the `www` pool has the following:
-
 ```ini
 [www]
 user = www-data
@@ -84,26 +121,12 @@ listen = /run/php/php7.4-fpm.sock
 listen.owner = www-data
 listen.group = www-data
 
-; How to Calculate the settings.
-; Read this article for details on full calculations + ps_mem.py script:
-; https://tideways.com/profiler/blog/an-introduction-to-php-fpm-tuning
-; wget https://raw.githubusercontent.com/pixelb/ps_mem/master/ps_mem.py
-;
-; | Setting            | Value                                               |
-; |:-------------------|:----------------------------------------------------|
-; | max_children       | (Total RAM - Memory used on server) / process size  |
-; |                    |              use 'free -hl' to get memory used      |
-; | start_servers      | Number of CPU cores x 4                             |
-; | min_spare_servers  | Number of CPU cores x 2                             |
-; | max_spare_servers  | Same as start_servers                               |
-;
-; Server Resources: 7.77G  | 331MB used | 4x CPU Cores
-; sudo python ps_mem.py | grep php-fpm
-; Used Memory: 24.8 MiB + 9.0 MiB = 33.7 MiB
-;
+; Server Resources: 8G RAM | 4x CPU Cores
+; `free -hl` output: Total 7.8Gi   Used 331Mi    Free 5.8Gi
+; `ps_mem.py` output: 24.8 MiB + 9.0 MiB = 33.7 MiB
 pm = dynamic
-; (Mem - Used) / ps_mem.py = Total Children
-; (7770 - 331) / 33.7 = 220.74
+; (Mem - Used) / ps_mem.py = max_children
+; (7800 - 331) / 33.7      = 221.63
 pm.max_children = 220
 ; CPU * 4 = 16
 pm.start_servers = 16
@@ -161,4 +184,7 @@ $ sudo nginx -t
 nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
 nginx: configuration file /etc/nginx/nginx.conf test is successful
 $ sudo systemctl reload nginx
-```
+```
+
+[tuning]: https://tideways.com/profiler/blog/an-introduction-to-php-fpm-tuning
+[psmem]: https://raw.githubusercontent.com/pixelb/ps_mem/master/ps_mem.py
diff --git a/6_sftp-setup.md b/6_sftp-setup.md
@@ -16,7 +16,7 @@ $ sudo chown -R FTPUSER:sftp /home/FTPUSER/.ssh
 $ sudo nano /etc/ssh/sshd_config
 ```
 
-```conf
+```nginx
 PubkeyAuthentication    yes
 Match group sftp
     X11Forwarding no

diff --git a/7_install-redis.md b/7_install-redis.md
@@ -14,7 +14,7 @@ $ sudo nano /etc/redis/redis.conf
 
 Change these settings:
 
-```nginx
+```ini
 supervised systemd # use Debian's systemd
 bind 127.0.0.1 ::1
 # If you want to secure your Redis server set a password below.

diff --git a/0_introduction.md b/0_introduction.md
@@ -8,16 +8,18 @@ These documents take you through each step of the configuration from:
 
 1. [General Setup][gen]
 1. [Install Linux, Nginx, MySQL, and PHP][lemp]
+1. [Confiure PHP and Nginx][config]
 1. [Create a new nginx vhost][vhost]
 1. [Setup Let's Encrypt SSL certificates][ssl]
 1. [Setup SFTP server][sftp]
+1. [Install Redis Server][redis]
 1. [Download and Configure phpMyAdmin][pma]
-1. [Install Redis][redis]
 
 [gen]: #file-1_general-md
 [lemp]: #file-2_install-lemp-md
-[vhost]: #file-3_new-vhost-md
-[ssl]: #file-4_setup-ssl-md
-[sftp]: #file-5_sftp-setup-md
-[pma]: #file-6_phpmyadmin-md
-[redis]: #file-7_install-redis-md
+[config]: #file-3_configure-php-nginx-md
+[vhost]: #file-4_new-vhost-md
+[ssl]: #file-5_setup-ssl-md
+[sftp]: #file-6_sftp-setup-md
+[redis]: #file-7_install-redis-md
+[pma]: #file-8_phpmyadmin-md
diff --git a/2_install-lemp.md b/2_install-lemp.md
@@ -44,97 +44,3 @@ $ sudo apt -y install php7.4-{fpm,cli,apc,bcmath,bz2,curl,gd,imagick,intl,mbstri
 $ sudo systemctl start php7.4-fpm
 $ sudo systemctl enable php7.4-fpm
 ```
-
-### Configure php.ini
-
-```console
-$ sudo nano /etc/php/7.4/fpm/php.ini
-```
-
-Change these values:
-
-```ini
-cgi.fix_pathinfo=0
-post_max_size=256M
-upload_max_filesize=256M
-date.timezone=Africa/Johannesburg
-[opcache]
-opcache.memory_consumption=256
-opcache.max_accelerated_files=10000
-opcache.validate_timestamps=120
-opcache.error_log=/var/log/opcache-errors.log
-[apc]
-apc.shm_size=128M
-apc.stat=1
-; Relative to the number of cached files (you may need to watch your stats for
-; a day or two to find out a good number).
-apc.num_files_hint=7000
-; The number of seconds a cache entry is allowed to idle in a slot before APC
-; dumps the cache.
-apc.ttl=7200
-apc.user_ttl=7200
-apc.include_once_override=0
-; Allow 2 seconds after a file is created before it is cached to prevent users
-; from seeing half-written/weird pages.
-apc.file_update_protection=2
-; Ignore files
-apc.filters = "/var/www/html/apc.php"
-apc.cache_by_default=1
-apc.use_request_time=1
-apc.slam_defense=0
-apc.stat_ctime=0
-apc.canonicalize=1
-apc.write_lock=1
-apc.report_autofilter=0
-apc.rfc1867=0
-apc.rfc1867_prefix=upload_
-apc.rfc1867_name=APC_UPLOAD_PROGRESS
-apc.rfc1867_freq=0
-apc.rfc1867_ttl=3600
-apc.lazy_classes=0
-apc.lazy_functions=0
-```
-
-```console
-$ sudo systemctl reload php7.4-fpm
-$ sudo systemctl reload nginx
-```
-
-### Configure nginx
-
-```console
-$ sudo nano /etc/nginx/nginx.conf
-```
-
-Change these values:
-
-```nginx
-client_max_body_size 128M;
-keepalive_timeout 2;
-server_tokens off;
-```
-
-Edit default host to enable PHP-FPM.
-
-```console
-$ sudo nano /etc/nginx/sites-available/default
-```
-
-Change these values:
-
-```nginx
-index index.php index.html index.htm index.nginx-debian.html;
-location ~ \.php$ {
-        include snippets/fastcgi-php.conf;
-        fastcgi_pass unix:/run/php/php7.4-fpm.sock;
-}
-```
-
-Test the output and reload.
-
-```console
-$ sudo nginx -t
-nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
-nginx: configuration file /etc/nginx/nginx.conf test is successful
-$ sudo systemctl reload nginx
-```
diff --git a/3_configure-php-nginx.md b/3_configure-php-nginx.md
@@ -0,0 +1,164 @@
+# Configure PHP-FPM and Nginx
+
+These are the different configuration files for setting up the servers.
+
+## Configure php.ini
+
+```console
+$ sudo nano /etc/php/7.4/fpm/php.ini
+```
+
+Change these values:
+
+```ini
+cgi.fix_pathinfo=0
+post_max_size=256M
+upload_max_filesize=256M
+date.timezone=Africa/Johannesburg
+[opcache]
+opcache.memory_consumption=256
+opcache.max_accelerated_files=10000
+opcache.validate_timestamps=120
+opcache.error_log=/var/log/opcache-errors.log
+[apc]
+apc.shm_size=128M
+apc.stat=1
+; Relative to the number of cached files (you may need to watch your stats for
+; a day or two to find out a good number).
+apc.num_files_hint=7000
+; The number of seconds a cache entry is allowed to idle in a slot before APC
+; dumps the cache.
+apc.ttl=7200
+apc.user_ttl=7200
+apc.include_once_override=0
+; Allow 2 seconds after a file is created before it is cached to prevent users
+; from seeing half-written/weird pages.
+apc.file_update_protection=2
+; Ignore files
+apc.filters = "/var/www/html/apc.php"
+apc.cache_by_default=1
+apc.use_request_time=1
+apc.slam_defense=0
+apc.stat_ctime=0
+apc.canonicalize=1
+apc.write_lock=1
+apc.report_autofilter=0
+apc.rfc1867=0
+apc.rfc1867_prefix=upload_
+apc.rfc1867_name=APC_UPLOAD_PROGRESS
+apc.rfc1867_freq=0
+apc.rfc1867_ttl=3600
+apc.lazy_classes=0
+apc.lazy_functions=0
+```
+
+```console
+$ sudo systemctl reload php7.4-fpm
+```
+
+## Configure php-fpm.conf
+
+```console
+$ sudo nano /etc/php/7.4/fpm/php-fpm.conf
+```
+
+```ini
+emergency_restart_threshold 10
+emergency_restart_interval 1m
+process_control_timeout 10s
+```
+
+## Configure php-fpm www.conf
+
+```console
+$ sudo nano /etc/php/7.4/fpm/pool.d/www.conf
+```
+
+Change so the `www` pool has the following:
+
+```ini
+[www]
+user = www-data
+group = www-data
+listen = /run/php/php7.4-fpm.sock
+listen.owner = www-data
+listen.group = www-data
+
+; How to Calculate the settings.
+; Read this article for details on full calculations + ps_mem.py script:
+; https://tideways.com/profiler/blog/an-introduction-to-php-fpm-tuning
+; wget https://raw.githubusercontent.com/pixelb/ps_mem/master/ps_mem.py
+;
+; | Setting            | Value                                               |
+; |:-------------------|:----------------------------------------------------|
+; | max_children       | (Total RAM - Memory used on server) / process size  |
+; |                    |              use 'free -hl' to get memory used      |
+; | start_servers      | Number of CPU cores x 4                             |
+; | min_spare_servers  | Number of CPU cores x 2                             |
+; | max_spare_servers  | Same as start_servers                               |
+;
+; Server Resources: 7.77G  | 331MB used | 4x CPU Cores
+; sudo python ps_mem.py | grep php-fpm
+; Used Memory: 24.8 MiB + 9.0 MiB = 33.7 MiB
+;
+pm = dynamic
+; (Mem - Used) / ps_mem.py = Total Children
+; (7770 - 331) / 33.7 = 220.74
+pm.max_children = 220
+; CPU * 4 = 16
+pm.start_servers = 16
+; CPU * 2 = 8
+pm.min_spare_servers = 8
+; Same as children
+pm.max_spare_servers = 16
+pm.max_requests = 500
+```
+
+```console
+$ sudo systemctl reload php7.4-fpm
+```
+
+## Configure nginx
+
+```console
+$ sudo nano /etc/nginx/nginx.conf
+```
+
+Change these values:
+
+```nginx
+client_max_body_size 128M;
+keepalive_timeout 2;
+server_tokens off;
+```
+
+```console
+$ sudo systemctl reload nginx
+```
+
+## Edit default host to enable PHP-FPM
+
+```console
+$ sudo nano /etc/nginx/sites-available/default
+```
+
+Change only these values in the host:
+
+```nginx
+server {
+    index index.php index.html index.htm index.nginx-debian.html;
+    location ~ \.php$ {
+            include snippets/fastcgi-php.conf;
+            fastcgi_pass unix:/run/php/php7.4-fpm.sock;
+    }
+}
+```
+
+Test the output and reload.
+
+```console
+$ sudo nginx -t
+nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
+nginx: configuration file /etc/nginx/nginx.conf test is successful
+$ sudo systemctl reload nginx
+```
diff --git a/3_new-vhost.md → 4_new-vhost.md b/3_new-vhost.md → 4_new-vhost.md
diff --git a/4_setup-ssl.md → 5_setup-ssl.md b/4_setup-ssl.md → 5_setup-ssl.md
diff --git a/5_sftp-setup.md → 6_sftp-setup.md b/5_sftp-setup.md → 6_sftp-setup.md
diff --git a/7_install-redis.md b/7_install-redis.md
@@ -14,7 +14,7 @@ $ sudo nano /etc/redis/redis.conf
 
 Change these settings:
 
-```env
+```nginx
 supervised systemd # use Debian's systemd
 bind 127.0.0.1 ::1
 # If you want to secure your Redis server set a password below.

diff --git a/6_phpmyadmin.md → 8_phpmyadmin.md b/6_phpmyadmin.md → 8_phpmyadmin.md
diff --git a/7_install-redis.md b/7_install-redis.md
@@ -14,7 +14,7 @@ $ sudo nano /etc/redis/redis.conf
 
 Change these settings:
 
-```config
+```env
 supervised systemd # use Debian's systemd
 bind 127.0.0.1 ::1
 # If you want to secure your Redis server set a password below.
@@ -23,7 +23,7 @@ bind 127.0.0.1 ::1
 
 ## Restart Redis
 
-```redis
+```console
 $ sudo systemctl restart redis
 $ sudo systemctl status redis
 ```