No outbound networking on Kubernetes pods
Maybe just double check that your node's ip forwarding is turned on: sysctl net.ipv4.ip_forward
If for some reason it doesn't return:net.ipv4.ip_forward = 1
Then you can set it with:sudo sysctl -w net.ipv4.ip_forward=1
And to make it permanent:
- edit
/etc/sysctl.conf - add or uncomment
net.ipv4.ip_forward = 1 - and reload via
sysctl -p /etc/sysctl.conf
Ok, so I was being stupid (or rather: a noob). I had an old iptables rule lying around on the host dropping all traffic on the FORWARD chain... removing that rule fixed the problem.
I feel a bit uneasy just removing that role but I have to admit that I don't fully understand the security implications of this. This might take some further research, but that's another topic. And since I'm not currently planning to run this cluster in production but rather use a hosted cluster, it's not really a problem anyways.