kURL: Diagnosing ip_forward being disabled

Hello,

I have a VM that has a couple of errors while doing the upgrade:

Error from server (BadRequest): container "kotsadm" in pod "kotsadm-0" is waiting to start: PodInitializing

or

Error from server (BadRequest): container "restore-db" in pod "kotsadm-57bd644c6f-f2ngx" is waiting to start: PodInitializing

Also, in coredns logs I see the following errors

failed to connect to postgres: failed to connect to postgres: failed to connect to `host=kotsadm-postgres user=kotsadm database=kotsadm`: hostname resolving error (lookup kotsadm-postgres on 10.100.0.10:53: dial udp 10.100.0.10:53: i/o timeout)
Error: failed to connect to postgres: failed to connect to postgres: failed to connect to `host=kotsadm-postgres user=kotsadm database=kotsadm`: hostname resolving error (lookup kotsadm-postgres on 10.100.0.10:53: dial udp 10.100.0.10:53: i/o timeout)

What could be causing these issues?

Generally, but not always, this happens when IP forward is disabled which is required for Docker to operate properly.

In order to diagnose this, run a few of the following commands:

  • systemctl status firewalld

    • Check to see if firewalld is disabled.
  • iptables -L -v

    • Double check to see no firewall rules are blocking.
  • docker info

    • At the bottom of the output see if there are any WARNINGs related to IPv4 forward being disabled.
  • sysctl -a

    • verify this is set to net.ipv4.ip_forward = 1
    • If its set to 0, set it to 1 using sysctl net.ipv4.ip_forward=1
    • Check to make sure /etc/sysctl.conf is also set to net.ipv4.ip_forward=1.