Hey for all of you hand-rolling a Kubernetes / Docker cluster, I thought I’d mention a bug with Centos 7.x that is still yet to be fixed. The error is:
/proc/sys/net/bridge/bridge-nf-call-iptables: No such file or directory.
The fix is simple. Just execute the following command (as root).
$ modprobe -v br_netfilter
Problem solved. If you don’t fix this problem and just ignore it, you won’t be able to resolve dns between your nodes. (There are probably a couple of other issues that can be associated with ignoring the error, but I wouldn’t know. I just noticed this problem during my build-out of the cluster and just **fixed** it.
To ensure that the module loads every time you reboot, run the following command:
echo "br_netfilter" > /etc/modules-load.d/00-br_netfilter.conf
Problem solved. Buy me a cookie 🙂
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