Did you try `umount -f`? I wouldn't say that is 'clean', but might avoid a reboot. It would seem there isn't much else that can be done if there is dirty data and no cluster to flush it to. This also looks relevant: http://tracker.ceph.com/issues/206 On Thu, Nov 28, 2013 at 9:51 PM, Ketor D <d.ketor@xxxxxxxxx> wrote: > Hi Sage: > We are testing cephfs mouting by kernel 3.12. And we meet a > situation that we cannot umount cephfs and also cannot reboot the > client machine. Only hard reset can restart the client machine. > Here is the flow: > 1) Create a ceph cluster with 3 mons, 2 mds (active-standby), 2 osds. > 2) Mount the cephfs with linux kernel 3.12. > 3) Using service ceph stop mon.x to stop all mons. > 4) Then we cannot umount the cephfs. The command lsof and > fuser cannot return,and even if we use "umount -l [mount_point]", we > only see the mount_point disappeared from /etc/mtab, but we still > cannot soft reboot the client machine. > > If we get in this situation, we can only hard reset the client > machine to avoid this. > So the problem is if there is some method can gracefully > umount the cephfs and dont make the client machine cant rebooted? > > Regards! > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html