Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Thu, Jul 07, 2016 at 07:16:51AM -0400, James Ault wrote: > Here is a scenario: > > Two identical servers running RHEL 6.7, > Three RAID5 targets, with one Logical volume group and one logical volume > defined on top of each target. > A DRBD device defined on top of each logical volume, and then an XFS file > system defined on top of each DRBD device. > > The two identical servers are right on top of one another in the rack, and > connected by a single ethernet cable for a private network. > > The configuration works as far as synchronization between DRBD devices. > > We do NOT have pacemaker as part of this configuration at management's > request. > > We have the XFS file system mounted on server1, and this file system is > exported via NFS. > > The difficulty lies in performing failover actions without pacemaker > automation. > > The file system is mounted, and those status flags on the file system are > successfully mirrored to server2. > > If I disconnected all wires from server1 to simulate system failure, and > promoted server2 to primary on one of these file systems, and attempted to > mount it, the error displayed is "file system already mounted". > > I have searched the xfs_admin and mount man pages thoroughly to find an > option that would help me overcome this state. > > Our purpose of replication is to preserve and recover data in case of > failure, but we are unable to recover or use the secondary copy in our > current configuration. > > How can I recover and use this data without introducing pacemaker to our > configuration? If you want to do manual failover (I believe we have that also documented in the User's Guide), all you do is drbdadm primary $res mount /dev/drbdX /some/where That's also exactly what pacemaker would do. If that does not work, you have it either "auto-mounted" already by something, or you have some file system UUID conflict, or something else is very wrong. -- : Lars Ellenberg : LINBIT | Keeping the Digital World Running : DRBD -- Heartbeat -- Corosync -- Pacemaker DRBD® and LINBIT® are registered trademarks of LINBIT __ please don't Cc me, but send to list -- I'm subscribed