Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Wednesday 08 April 2009 18:38:54 you wrote: > > A crucial factor is wether you can tolerate stale data. Running rsync > > periodically will probably result in not-quite-uptodate replication when > > the storm troopers come rushing in and cut your power. If that is not a > > concern, eg. because your data doesn't change all that often, or you > > simply don't care about a few lost updates, then rsync is IMHO simpler to > > set up. > > > > In contrast, DRBD does real replication. Depending on your link/network > > quality and the chosen protocol you can guarantee that local writes are > > only considered complete if the remote side also has completed. > > Maybe it is a re-incarnation of executive order 6102, to melt down the > servers for their gold content? > > Anyhow, provided the bandwidth is sufficient, I prefer the DRBD > option. However, will the backups be successful, if the backup drive > is attached to the secondary? Most of what I've read suggests that > you shouldn't even mount the secondary in read-only mode (although > maybe an LVM snapshot can be mounted for taking a backup). DRBD won't allow you to mount a secondary. This means you either have to use a Dual Primary setup (requiring a cluster filesystem) or make a block-level backup (don't know if thats adivsable). Maybe you can temporarily disconnect DRBD for the backup, promote the secondary, mount + backup, demote again, and reconnect -- Im not really sure if this would work though, you'd have to try. peter. > For databases, I intend to dump them to text files at least an hour > before attempting to make a backup of the secondary. This gives me > something to fall back on if the raw files are not in a consistent > state on the secondary. -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 197 bytes Desc: This is a digitally signed message part. URL: <http://lists.linbit.com/pipermail/drbd-user/attachments/20090408/71d9b4bc/attachment.pgp>