We currently use LVM2 snapshots to backup a MySQL database. To quiesce our database we issue a 'flush tables with read lock', then snapshot, then release the lock. This approach yields consistent snapshots of our database. We do our snapshot in a Perl script. This allows us to create and hold a connection to the database during the entire flush, snapshot, unlock process. I don't think you'll be able to do that directly in ksh. The 'flush tables with read lock' only persists as long as the connection is active. On 8/17/05, Lutz.Reinegger@t-systems.com <Lutz.Reinegger@t-systems.com> wrote: > Hey there, > > currently I am testing a small backup script (ksh) which is supposed to create snapshots > of my MySQL database file systems using the Linux LVM2 snapshot feature. > > Here is the command I am using: > "/usr/sbin/lvcreate -L 10240M --snapshot -p r -n mysqlsnap /dev/datavg/mysqllv" > > It works fine so far ($? = 0), however I am seeing some kind of strange messages: > " > File descriptor 7 left open > Logical volume "mysqlsnap" created > " > > A month ago Jürgen reported similar messages using "lvdisplay": > https://www.redhat.com/archives/linux-lvm/2005-July/msg00069.html > Alasdair then pointed out that this message is (only?) a warning message: > https://www.redhat.com/archives/linux-lvm/2005-July/msg00070.html > > Here 's my question: > Do I have to be worried about the consistency of my snapshots in any way > because of this message? > > Operating system : RedHat Enterprise Linux 4 for IA32 + latest patches. > Kernel version : 2.6.9-11.ELsmp > > lvm> version > LVM version : 2.01.08 (2005-03-22) > Library version : 1.01.01 (2005-03-29) > Driver version : 4.4.0 > lvm> > > Kind regards > Lutz Reinegger > > _______________________________________________ > linux-lvm mailing list > linux-lvm@redhat.com > https://www.redhat.com/mailman/listinfo/linux-lvm > read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ > _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
