On Wed, May 21, 2008 at 02:41:59PM +0300, Ehud Karni wrote: > If you have enough disk space you can create "pseudo" snapshots by > using hardlinks between the snapshots so only changed file takes space. > It really depends on the file size distribution - few large files that > change constantly will defeat this concept, while many small files is > ideal for this scenario. > > I use this approach and keep more than 60 "snapshots" of 350 GB disk > on a 700 GB disk. > > The whole process is very simple: > Initiation: copy the whole disk (or an LVM snapshot of it) to the > destination disk in a SUBDIRECTORY (eg `cp -a'). > > For each snapshot: > 1. Check the size left on the "snapshot" disk and remove old > "snapshot"s until you have predefined minimum space. > 2. Copy the subdir (hardlink only) to a new subdir (I use `cp -al'). > 3. Create an LVM snapshot of the original system. > 4. Sync the copied subdir with the real LVM snapshot (`rsync'). > 5. Remove the LVM snapshot. > > I can send you a script we use on our system but most of it is our > specific details.
There are also "packaged" scripts that do something like this. I personally use rsnapshot, there are a few others. -- Didi ================================================================= To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
