I learned today that psadump (Plesk backup utility) stops services when dumping the files into the backup. This behavior can be turned off (-nostop flag or something like that) but this is its default behavior.
I understand that it is safer to do the backup when the system is in stable state since services can't change files during the backup process because they are stopped. But on the other hand, the server becomes unavailable for some time.
What is your opinion on this? Should I keep using this default behavior that stops services, or turn it off?
it is only for the site that is being dumped. I wouldn't disable it. As long as end-users know that this is happening, IIRC it notifies you, then they are acknowledging and therefore, they shouldn't mind. It is very brief as well.
Well, what do you want? A backup of your site that might be edited as the backup runs? Or the safe backup of the site.
With plesk you get to choose - put the --nostop option on if you want.
Personally, I backup all the sites in a cron job.. at 4am. Nobody's complained yet
If it is a problem, and you have a lot of database data, MySql recommends making a replication slave DB, and taking backups of that. Combine that with a rsync backup of your Plesk directories and you should see faster backups.
Originally posted by gbjbaanb Well, what do you want? A backup of your site that might be edited as the backup runs?
Yes, I understand that a system must be in the "frozen" state in order to be backed up correctly, and that taking snapshots of a dynamic system in action is not a good idea. I was just asking if this is the usual way of doing Plesk backups.
By the way, this is why I don't trust image-based backups (like Acronis for Linux) -- they take a snapshot of a working, changing hard drive. What if they grab a sector which is currently being written? And what if that sector belongs to a DB file?