5 Verificações simples

Visão geral

Verificações simples são normalmente usadas para verificações remotas de serviço, sem agente.

Note que o Zabbix Agent não é necessário para verificações simples. O Zabbix Server/Proxy é responsável pelo processamento das verificações simples (fazendo conexões externas, etc.).

Exemplos de uso de verificações simples:

net.tcp.service[ftp,,155]
       net.tcp.service[http]
       net.tcp.service.perf[http,,8080]
       net.udp.service.perf[ntp]

Verificações simples suportadas

Lista de verificações simples suportadas:

Veja também:

• Chaves de item de monitoramento VMware

Item key details

icmpping[<target>,<packets>,<interval>,<size>,<timeout>,<options>]

The host accessibility by ICMP ping.
Return value: 0 - ICMP ping fails; 1 - ICMP ping successful.

Parameters:

• target - the host IP or DNS name;
• packets - the number of packets;
• interval - the time between successive packets in milliseconds;
• size - the packet size in bytes;
• timeout - the timeout in milliseconds;
• options - used for allowing redirect: if empty (default value), redirected responses are treated as target host down; if set to allow_redirect, redirected responses are treated as target host up.

See also the table of default values.

Example:

icmpping[,4] #If at least one packet of the four is returned, the item will return 1.

icmppingloss[<target>,<packets>,<interval>,<size>,<timeout>,<options>]

The percentage of lost packets.
Return value: Float.

Parameters:

• target - the host IP or DNS name;
• packets - the number of packets;
• interval - the time between successive packets in milliseconds;
• size - the packet size in bytes;
• timeout - the timeout in milliseconds;
• options - used for allowing redirect: if empty (default value), redirected responses are treated as target host down; if set to allow_redirect, redirected responses are treated as target host up.

See also the table of default values.

icmppingsec[<target>,<packets>,<interval>,<size>,<timeout>,<mode>,<options>]

The ICMP ping response time (in seconds).
Return value: Float.

Parameters:

• target - the host IP or DNS name;
• packets - the number of packets;
• interval - the time between successive packets in milliseconds;
• size - the packet size in bytes;
• timeout - the timeout in milliseconds;
• mode - possible values: min, max, or avg (default);
• options - used for allowing redirect: if empty (default value), redirected responses are treated as target host down; if set to allow_redirect, redirected responses are treated as target host up.

Comments:

• Packets which are lost or timed out are not used in the calculation;
• If the host is not available (timeout reached), the item will return 0;
• If the return value is less than 0.0001 seconds, the value will be set to 0.0001 seconds;
• See also the table of default values.

net.tcp.service[service,<ip>,<port>]

Checks if a service is running and accepting TCP connections.
Return value: 0 - the service is down; 1 - the service is running.

Parameters:

• service - possible values: ssh, ldap, smtp, ftp, http, pop, nntp, imap, tcp, https, telnet (see details);
• ip - the IP address or DNS name (by default the host IP/DNS is used);
• port - the port number (by default the standard service port number is used).

Comments:

• Note that with tcp service indicating the port is mandatory;
• These checks may result in additional messages in system daemon logfiles (SMTP and SSH sessions being logged usually);
• Checking of encrypted protocols (like IMAP on port 993 or POP on port 995) is currently not supported. As a workaround, please use net.tcp.service[tcp,<ip>,port] for checks like these.

Example:

net.tcp.service[ftp,,45] #This item can be used to test the availability of FTP server on TCP port 45.

net.tcp.service.perf[service,<ip>,<port>]

Checks the performance of a TCP service.
Return value: Float: 0.000000 - the service is down; seconds - the number of seconds spent while connecting to the service.

Parameters:

• service - possible values: ssh, ldap, smtp, ftp, http, pop, nntp, imap, tcp, https, telnet (see details);
• ip - the IP address or DNS name (by default the host IP/DNS is used);
• port - the port number (by default the standard service port number is used).

Comments:

• Note that with tcp service indicating the port is mandatory;
• Checking of encrypted protocols (like IMAP on port 993 or POP on port 995) is currently not supported. As a workaround, please use net.tcp.service[tcp,<ip>,port] for checks like these.

Example:

net.tcp.service.perf[ssh] #This item can be used to test the speed of initial response from SSH server.

net.udp.service[service,<ip>,<port>]

Checks if a service is running and responding to UDP requests.
Return value: 0 - the service is down; 1 - the service is running.

Parameters:

• service - possible values: ntp (see details);
• ip - the IP address or DNS name (by default the host IP/DNS is used);
• port - the port number (by default the standard service port number is used).

Example:

net.udp.service[ntp,,45] #This item can be used to test the availability of NTP service on UDP port 45.

net.udp.service.perf[service,<ip>,<port>]

Checks the performance of a UDP service.
Return value: Float: 0.000000 - the service is down; seconds - the number of seconds spent waiting for response from the service.

Parameters:

• service - possible values: ntp (see details);
• ip - the IP address or DNS name (by default the host IP/DNS is used);
• port - the port number (by default the standard service port number is used).

Example:

net.udp.service.perf[ntp] #This item can be used to test the response time from NTP service.

Note that for SourceIP support in LDAP simple checks, OpenLDAP version 2.6.1 or above is required.

Tempo limite de processamento

O Zabbix não processará uma verificação simples por mais tempo do que os segundos de limite (Timeout) definidos no arquivo de configuração do Zabbix Server/Proxy.

Ping ICMP

O Zabbix usa o utilitário externo fping para processar os pings ICMP.

O utilitário não faz parte da distribuição do Zabbix e precisa ser instalado individualmente. Se ele estiver ausente, com permissões insuficientes ou sua localização for diferente do valor definido no arquivo de configuração do Zabbix Server (parâmetro 'FpingLocation'), os itens de ICMP (icmpping, icmppingloss, icmppingsec) não serão processados.

Veja também: problemas conhecidos

O fping precisa ser executável pelos daemons do Zabbix rodando com 'setuid' do root. Execute estes comandos como root para configurar corretamente as permissões:

shell> chown root:zabbix /usr/sbin/fping
       shell> chmod 4710 /usr/sbin/fping

Após executar os dois comandos acima, verifique o proprietário do executável fping. Em alguns casos o proprietário pode ser reconfigurado executando o comando chmod.

Verifique também se o usuário zabbix pertence ao grupo zabbix executando:

shell> groups zabbix

e se não pertencer, adicione-o da seguinte forma:

shell> usermod -a -G zabbix zabbix

Padrões, limites e descrições dos valores para os parâmetros de verificações ICMP:

|Parâmetro|Unidade|Descrição|Fping's flag|Padrões definidos por|<|Limites permitidos
pelo Zabbix|<| |---------|----|-----------|------------|--------- ------|-|---------------------------|-| |||||fping|Zabbix|min|max| |pacotes|number|número de pacotes de solicitação para um destino|-C||3|1|10000| |intervalo|milissegundos|tempo de espera entre pacotes sucessivos|-p|1000||20|ilimitado| |tamanho|bytes|tamanho do pacote em bytes
56 bytes em x86, 68 bytes em x86_64|-b|56 ou 68||24|65507| |tempo limite|milissegundos|fping v3.x - tempo limite de espera após o último pacote enviado, afetado pelo sinalizador -C
fping v4.x - tempo limite individual para cada pacote|-t| fping v3.x - 500
fping v4.x - herdado do sinalizador -p, mas não superior a 2000||50|ilimitado|

Além disso, o Zabbix usa as opções de fping -i interval ms (não confunda com o parâmetro de item intervalo mencionado na tabela acima, que corresponde à opção de fping -p) e endereço IP de origem -S (ou -I em versões mais antigas de fping). Essas opções são detectadas automaticamente executando verificações com diferentes combinações de opções. O Zabbix tenta detectar o valor mínimo em milissegundos que o fping permite usar com -i tentando 3 valores: 0, 1 e 10. O primeiro valor bem-sucedido é então usado para verificações ICMP subsequentes. Esta ação é executada por cada processo de ping ICMP individualmente.

As opções de fping detectadas automaticamente são invalidadas a cada hora e detectadas novamente na próxima tentativa de realizar a verificação ICMP. Defina DebugLevel>=4 para visualizar os detalhes desse processo no arquivo de log do Zabbix Server ou Proxy.

O Zabbix grava os endereços IP a serem verificados por qualquer uma das três chaves icmpping* em um arquivo temporário, que é então passado para o fping. Se os itens têm parâmetros de chave diferentes, apenas aqueles com parâmetros de chave idênticos são gravados em um único arquivo.
Todos os endereços IP gravados no arquivo único serão verificados pelo fping em paralelo, então o processo de ping icmp do Zabbix levará uma quantidade fixa de tempo, desconsiderando o número de endereços IP no arquivo.

Installation

fping is not included with Zabbix and needs to be installed separately:

• Various Unix-based platforms have the fping package in their default repositories, but it is not pre-installed. In this case you can use the package manager to install fping.

• Zabbix provides fping packages for RHEL. Please note that these packages are provided without official support.

• fping can also be compiled from source.

Configuration

Specify fping location in the FpingLocation parameter of Zabbix server/proxy configuration file (or Fping6Location parameter for using IPv6 addresses).

fping should be executable by the user Zabbix server/proxy run as and this user should have sufficient rights.

See also: Known issues for processing simple checks with fping versions below 3.10.

Default values

Defaults, limits and description of values for ICMP check parameters:

The defaults may differ slightly depending on the platform and version.

In addition, Zabbix uses fping options -i interval ms (do not mix up with the item parameter interval mentioned in the table above, which corresponds to fping option -p) and -S source IP address (or -I in older fping versions). These options are auto-detected by running checks with different option combinations. Zabbix tries to detect the minimal value in milliseconds that fping allows to use with -i by trying 3 values: 0, 1 and 10. The value that first succeeds is then used for subsequent ICMP checks. This process is done by each ICMP pinger process individually.

Auto-detected fping options are invalidated every hour and detected again on the next attempt to perform ICMP check. Set DebugLevel>=4 in order to view details of this process in the server or proxy log file.

Zabbix writes IP addresses to be checked by any of the three icmpping* keys to a temporary file, which is then passed to fping. If items have different key parameters, only the ones with identical key parameters are written to a single file. All IP addresses written to the single file will be checked by fping in parallel, so Zabbix ICMP pinger process will spend fixed amount of time disregarding the number of IP addresses in the file.