Red Hat 7 not supported anymore?

Installing K3s v1.24.3+k3s1 on a RHEL 7.9 system fails:

  • As the first master node, all pods remain in ContainerCreating indefinitely
  • As an additional master node the traefik pod remains in ContainerCreating indefinitely

The following event probably indicates what the problem is:

Warning FailedCreatePodSandBox pod/metrics-server-668d979685-4dzkm Failed to create pod sandbox: rpc error: code = Unknown desc = failed to create containerd task: failed to create shim task: OCI runtime create failed: runc create failed: unable to start container process: error during container init: open /proc/sys/net/ipv4/ip_unprivileged_port_start: no such file or directory: unknown

According to the information I could find about this error, the ip_unprivileged_port_start entry in /proc/sys/net/ipv4/ only exists in Linux kernel 4.4 and newer, so it seems that the latest Red Hat 7 release (7.9) is not supported anymore. Or am I missing something?

If this is true, Debian 9 (stretch) is also not supported anymore as it is also missing this entry.

Although the the support matrix is mainly for rancher, i think it can be applied to k3s alone.
Support matrix
And according to this document look like the higher k3s version that you can run on rhel 7.9 is k3s+1.23.x

But this support matrix does not list version k3s+1.24 at all, even for rhel 8.x, so I’ll just have to wait for the support matrix to be updated before we now for sure …