Greetings, Fajar A. Nugraha! >>> thank you for sharing Fajar, this is very helpful. A couple questions: >>> 1. how do you ensure data consistency? I don't think it's safe to take a >>> snap of a mysql container with mysql running for example. Other backup >>> solutions I've used in the past, like bacula for example, allowed you to run >>> pre-backup jobs to say make the db readonly or stuff like that. Are you >>> doing such a thing with sanoid? >>> 2. related to, if you move lib/lxd, is it safe to snap with lxd running? no >>> consistency issues? >> >> It is never a good idea to snapshot the disk of a running system.
> On an ideal world, sure. > In reality, when your options are limited between "shutdown your apps every > night before backups" or "perform storage-level-snapshot which doesn't > interfere with the running system and can be brought to consistent state", I > chose the later. >> Any files opened for writing are unlikely to backup properly. > Filesystem and database journaling is written with that in mind, so they > can safely deal with (e.g.) half-(over)written files. Yes, on a filesystem level. No on application level. Exception is when application makes sure that its writes are consistent, like databases do. >> It is less of an issue for MySQL and other applications that use journaling >> for their write operations, but on any given live system there's more apps >> that don't expect power interruptions. > If you have one of those apps, I highly recommend you fix it, or find > another one that behave correctly. You don't want to be left out cold when a > real power interruption (or server crash) happens. The app behaves correctly, in its own right. -- With best regards, Andrey Repin Wednesday, May 3, 2017 20:08:05 Sorry for my terrible english... _______________________________________________ lxc-users mailing list [email protected] http://lists.linuxcontainers.org/listinfo/lxc-users
