In ipv6-only cluster with proxy-mode=ipvs ipv4 entries are used for NodePort #68437
Description
Is this a BUG REPORT or FEATURE REQUEST?:
/kind bug
/area ipv6
/area ipvs
/sig network
What happened:
In an ipv6-only cluster with proxy-mode=ipvs the entries for NodePort in ipvs are created for ipv4 addresses. The target's (if there are any) consists of ipv6 addresses (wrongly) interpreted as ipv4;
# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
cgen NodePort fd00:4000::c698 1000::2 5001:30669/TCP 42m
...
# ipvsadm -L -n
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 127.0.0.1:30669 rr
-> 253.0.48.0:5001 Masq 1 0 0
TCP 192.168.0.4:30669 rr
-> 253.0.48.0:5001 Masq 1 0 0
TCP [fd00:4000::c698]:5001 rr
-> [fd00:3000:1::2]:5001 Masq 1 0 0
-> [fd00:3000:2::2]:5001
...
Attempts to use the NodePort with ipv6 addresses are black-holed.
What you expected to happen:
Ipv6 addresses to the nodes should be used for NotePort and the LB-targets shall be the ipv6 address of the pods. Traffic to NodePorts shall be distributed among the (ipv6) endpoints.
How to reproduce it (as minimally and precisely as possible):
- Setup an ipv6-only cluster
- Create a service with type
NodePortwith endpoints - Try to connect to the NodePort
- Do
ipvsadm -L -n
Anything else we need to know?:
The nodes have both ipv4 and ipv6 addresses and it is possible that if the nodes only had ipv6 addresses it would work (I havn't tested). But even in an ipv6-only k8s cluster the nodes almost always need ipv4 addresses for other purposes.
Environment:
- Kubernetes version (use
kubectl version):
# kubectl version
Client Version: version.Info{Major:"1", Minor:"13+", GitVersion:"v1.13.0-alpha.0.1136+edd4fc25330c7f", GitCommit:"edd4fc25330c7fba7f0fd8a127b872c8614c7363", GitTreeState:"clean", BuildDate:"2018-09-07T16:28:26Z", GoVersion:"go1.10.4", Compiler:"gc", Platform:"linux/amd64"}
Server Version: version.Info{Major:"1", Minor:"13+", GitVersion:"v1.13.0-alpha.0.1136+edd4fc25330c7f", GitCommit:"edd4fc25330c7fba7f0fd8a127b872c8614c7363", GitTreeState:"clean", BuildDate:"2018-09-07T16:27:51Z", GoVersion:"go1.10.4", Compiler:"gc", Platform:"linux/amd64"}
- Cloud provider or hardware configuration:
Kvm VMs on Ubuntu 18.04.01 LTS - OS (e.g. from /etc/os-release):
Own BusyBox based system - Kernel (e.g.
uname -a):
# uname -a
Linux vm-004 4.18.5 #1 SMP Fri Sep 7 14:40:23 CEST 2018 x86_64 GNU/Linux
- Install tools:
None - Others: