On Wed, 29 Aug 2012, Andrew McGlashan <andrew.mcglashan@affinityvision.com.au> wrote:
Unless I am mistaken, all Shadow Protect does is create snapshot of the filesystem at a point in time. No different to taking an LVM snapshot.
AFAIK the only ways of making a snapshot on Linux are LVM (which is supported everywhere - including RHEL), BTRFS (experimental everywhere except Oracle and "tech preview" in RHEL), and ZFS (reliable but not supported in RHEL). Unless Shadow Protect uses LVM snapshots I don't think it can do what you claim.
If at that point in time there are processes still with open files and data in memory, then you have every risk of corruption and lack of a suitable backup.
No, if you have all MySQL data on a single filesystem then you should be safe with an LVM snapshot.
Lots to consider, are you using Xen, KVM or any other virtualization in your setup? Are you using RAID1 and can you shutdown briefly, disconnect a drive from RAID1 (preferably with 3 or more RAID members in normal operation). LVM snapshots are also a good option. I shutdown entire VM's just long enough to snapshot all file systems, then restart the VM and proceed with backing up off the snapshots.
How many and what type of disks make up the 6TB ? How are they set up?
6TB wouldn't be a RAID-1. On Wed, 29 Aug 2012, "Trent W. Buck" <trentbuck@gmail.com> wrote:
The other way you can do it, is tell rsync to exclude the "real" database files, and don't worry if they're incoherent, because you have a daily cron job that tells the db to make a coherent dump of itself to a local file, which rsync will back up.
That is very good for a small database. For my blog I have a cron job which dumps the database and another cron job on a workstation to copy the daily dump file. Then the directory full of daily dump files is part of the workstation backup. This is for a dump file that's 5.6M compressed. When you have a big database (or even a database that's a few gigs in size) you don't necessarily want to wait for a dump to be loaded before going live. -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/