I would still set noout on relevant parts of the cluster in case something goes south and it does take longer than 2 minutes. Otherwise OSDs will start outing themselves after 10 minutes or so by default and then you have a lot of churn going on. The monitors monitors will be fine unless you lose quorum, but even so they'll just recover once the switch comes back. You just won't be able to make changes to the cluster if you lose mon quorum, nor will the OSDs start recovering etc. until that occurs. Depending on which version of Ceph/libvirt/etc. you are running, I have seen issues with older releases of the same where a handful of VMs get indefinitely stuck with really high I/Owait afterwards and needed to be manually rebooted on occasion when doing something like this. As another user mentioned, the kernels softlockup handler kicks in after 120 seconds by default so you'll see lots of stacktraces in the VMs due to processes blocked on I/O if the reboot and repeering doesn't all happen within exactly two minutes. If you can afford to shutdown all the VMs in the cluster, it might be for the best as they'll be losing I/O... On Tue, Jan 25, 2022, 4:27 AM Marc <Marc@xxxxxxxxxxxxxxxxx> wrote: > > If the switch needs an update and needs to be restarted (expected 2 > minutes). Can I just leave the cluster as it is, because ceph will handle > this correctly? Or should I eg. put some vm's I am running in pause mode, > or even stop them. What happens to the monitors? Can they handle this, or > maybe better to switch from 3 to 1 one? > > > > > > > > > _______________________________________________ > ceph-users mailing list -- ceph-users@xxxxxxx > To unsubscribe send an email to ceph-users-leave@xxxxxxx > _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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