Hi,

I really like the tool, thank you. also confirms my idea as this kernel option is also used by other projects where they explicitly mention case with keepalived/VIP switch.

Now I definitively think this should be handled also in kolla-ansible.

Thanks,

Michal Arbet ( kevko )

Dne po 1. 3. 2021 9:53 uživatel Mark Goddard <mark@stackhpc.com> napsal:

On Fri, 26 Feb 2021 at 17:08, Michal Arbet <michal.arbet@ultimum.io> wrote:
>
> Hi,
>
> I found that keepalived VIP switch cause TCP connections that refuse to die on host where VIP was before it was switched.
>
> I filled a bug here -> https://bugs.launchpad.net/kolla-ansible/+bug/1917068
> Fixed here -> https://review.opendev.org/c/openstack/kolla-ansible/+/777772
> Video presentation of bug here -> https://download.kevko.ultimum.cloud/video_debug.mp4
>
> I was just curious and wanted to ask here in openstack-discuss :
>
> If someone already seen this issue in past ?
> If yes, do you tweak net.ipv4.tcp_retries2 kernel parameter ?
> If no, how did you solve this ?

Hi Michal, thanks for the investigation here. There is a nice tool,
that I found far too late, that helps to help answer questions like
this: https://codesearch.opendev.org/

>
> Thank you,
> Michal Arbet ( kevko )
>