> Op 26 okt. 2022 om 10:11 heeft mj <li...@merit.unu.edu> het volgende > geschreven: > > Hi! > > We have read https://docs.ceph.com/en/latest/man/8/mount.ceph, and would like > to see our expectations confirmed (or denied) here. :-) > > Suppose we build a three-node cluster, three monitors, three MDSs, etc, in > order to export a cephfs to multiple client nodes. > > On the (RHEL8) clients (web application servers) fstab, we will mount the > cephfs like: > >> cehp1,ceph2,ceph3:/ /mnt/ha-pool/ ceph >> name=admin,secretfile=/etc/ceph/admin.secret,noatime 0 2 > > We expect that the RHEL clients will then be able to use (read/write) a > shared /mnt/ha-pool directory simultaneously. > > Our question: how HA can we expect this setup to be? Looking for some > practical experience here. > > Specific: Can we reboot any of the three involved ceph servers without the > clients noticing anything? Or will there be certain timeouts involved, during > which /mnt/ha-pool/ will appear unresposive, and *after* a timeout the client > switches monitor node, and /mnt/ha-pool/ will respond again?
Monitor failovers don’t cause a noticeable disruption IIRC. MDS failovers do. The MDS needs to replay. You can minimise the effect with mds_standby_replay. > > Of course we hope the answer is: in such a setup, cephfs clients should not > notice a reboot at all. :-) > > All the best! > > MJ > _______________________________________________ > ceph-users mailing list -- ceph-users@ceph.io > To unsubscribe send an email to ceph-users-le...@ceph.io > _______________________________________________ ceph-users mailing list -- ceph-users@ceph.io To unsubscribe send an email to ceph-users-le...@ceph.io
