Re: LVM-snapshot + mysqldump -- is this a reasonable backup

[George Herson]

James G. Sack (jim) wrote: On Mon, 2005-09-19 at 13:14 -0400, George Herson wrote: James G. Sack (jim) wrote: On Mon, 2005-09-19 at 12:15 -0400, George Herson wrote: Dear Jim, Re: your post at http://lists.mysql.com/mysql/189058, why bother creating the mysqldump if you already have the snapshot? Why not just backup the snapshot? [...] The output of mysqldump *is* the backup. If the db goes away, it can be restored with (something like) "mysql <dumpfile.2005-09-01". The dump operation is run periodically, and some number of back versions can be kept around (or offloaded) for archival value. Yes, but can't you also save your snapshot instead, then, when/if you want, restore it, "4. mount the snapshot 5. load a second database server daemon accessing the db within the snapshot (with a suitable alternate my.cnf file) 6. perform mysqldump operation on the snapshot-db" ?? .. George, LVM snapshots are generally intended to be short-lived -- <snip> ..jim Jim, I didn't word my question quite right because I was only guessing at what a LVM snapshot was. Moreover, what you're saying is all correct.  However, I was not suggesting that the snapshot be kept around once the backup is made.  Let's go to article "What is a Logical Volume Manager (LVM) snapshot and how do I use it?" in the RedHat k'base.  It says "After performing the backup of the snapshot partition we release the snapshot".  This implies, at least to me, that one doesn't need a 2nd database server or to do a mysqldump (your steps 5-7).  Instead, we just tar cv /mnt/ops/dbbackup (to use the article's example name for the mounted snapshot), save the tape, and dispense with the snapshot. Wouldn't that work?  MySQL keeps its data in files already, so why is it necessary to mysqldump it?  Are you only trying to avoid having to also backup the mysqld version that wrote the data files to ensure that these can be read later? George

-- 
MySQL General Mailing List
For list archives: http://lists.mysql.com/mysql
To unsubscribe:    http://lists.mysql.com/[EMAIL PROTECTED]