> The one thing that I keep thinking, and which I have yet to see > discredited, is that > ZFS file systems use POSIX semantics. So, unless you are using > specific features > (notably ACLs, as Paul Henson is), you should be able to backup those > file systems > using well known tools.
This is correct. Many people do backup using tar, star, rsync, etc. > The Best Practices Guide is also very clear about send and receive NOT > being > designed explicitly for backup purposes. I find it odd that so many > people seem to > want to force this point. ZFS appears to have been designed to allow > the use of > well known tools that are available today to perform backups and > restores. I'm not > sure how many people are actually using NFS v4 style ACLs, but those > people have > the most to worry about when it comes to using tar or NetBackup or > Networker or > Amanda or Bacula or star to backup ZFS file systems. Everyone else, > which appears > to be the majority of people, have many tools to choose from, tools > they've used > for a long time in various environments on various platforms. The > learning curve > doesn't appear to be as steep as most people seem to make it out to > be. I honestly > think many people may be making this issue more complex than it needs > to be. I think what you're saying is: Why bother trying to backup with "zfs send" when the recommended practice, fully supportable, is to use other tools for backup, such as tar, star, Amanda, bacula, etc. Right? The answer to this is very simple. #1 "zfs send" is much faster. Particularly for incrementals on large numbers of files. #2 "zfs send" will support every feature of the filesystem, including things like filesystem properties, hard links, symlinks, and objects which are not files, such as character special objects, fifo pipes, and so on. Not to mention ACL's. If you're considering some other tool (rsync, star, etc), you have to read the man pages very carefully to formulate the exact backup command, and there's no guarantee you'll find a perfect backup command. There is a certain amount of comfort knowing that the people who wrote "zfs send" are the same people who wrote the filesystem. It's simple, and with no arguments, and no messing around with man page research, it's guaranteed to make a perfect copy of the whole filesystem. Did I mention fast? ;-) Prior to zfs, I backed up my file server via rsync. It's 1TB of mostly tiny files, and it ran for 10 hours every night, plus 30 hours every weekend. Now, I use zfs send, and it runs for an average 7 minutes every night, depending on how much data changed that day, and I don't know - 20 hours I guess - every month. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
