Solution needed for INCR backup since last DIFF, or multi-level incremental

[geva]

Hello all:

It seems that I have misunderstood the definition of a differential backup - specifically that it does not reset the archive bit, and will thusly be unrelated to incremental backups.  Other backup vendors do not define it as such, and neither does wikipedia (they say since last backup - not since last FULL or INCR backup).

My problem is that I would like weekly backups that encompass all data that has changed since the last full backup.  As the backups are being moved over a WAN link, I cannot be doing more full backups than absolutely necessary.  The idea is to have monthly full backups, weekly "differential" backups, and then daily incremental backups backing up data changed since the last backup.

The problem that I have is that differential backups don't work this way, and I need to backup the same data twice (file 1 changes, gets backed up in DIFF, and then in INCR).  This is a big problem, as there is one file that is over 3Gb (a Symantec SEPM DB file!).

I would be open to only backing this file up on the weekend, however I cannot do that, as I need to use the same selection list for all FULL, DIFF, INCR backups. :(  It's nice to have the selection list managed in one place, but it would be nice to exclude files from a particular job.

A couple hours of research has shown that such a solution should be possible, and might be better called a multi-level incremental backup (see wiki).  Another option would simply be another option in the incremental backup type - "incremental backup using modified time since last differential backup".

Any assistance or suggestions are appreciated.  I've been working on this for many months and it seems that I just keep running across one thing after another.

Thanks,

geva

p.s. customer is using BE 12.5 SBS; looked at moving to 2010 w/ Deduplication, however some previous bad choices don't leave this as an option

[pkh]

Are you using an SQL agent to backup the SEPM database?  If you are then you should stop and follow this procedure to backup the SEPM database

http://www.symantec.com/docs/TECH96409

This will create a backup will in the SEPM installation directory.  I have been told by Tech Support not to use the SQL agent to backup the SEPM database directly.

Do not mix differential and incremental backups!  More often than not, without a full understanding of what files are backed up, you would find yourself in a situation where your backups are incomplete.  Also, it becomes very complicated when it is time to restore the system.  You would get confused by which backups, full, incremental or differential backups to restore and in which sequence.

Stick to one backup scheme, either full + differential or full + incremental.

[Ken_Putnam]

Completely agree with pkh

In a BackupExec environement DO NOT MIX DIFF & INCR.

I understand the problems involved with FULL backups when large amounts of data are involved, but usually you can start your FULL after COB on Friday and get it done by Monday morning, then do either DIFF or INCR the rest of the week. 

Also, BackupExec is notoriously fragile when doing remote backups over a WAN link, (unless they've greatly inproved the RAWS in the last version or two)  If you can wangle it into the budget, I'd highly recommend a second media server in the remote office

Dedupe would also help solve the problem, as it would transfer much less data over the WAN link.  "Seed" your remote server in your main office by doing the first backup there, then take it to the remote site and let DeDupe take over

[teiva-boy]

Without checkpoint restart like Netbackup and other enterprise backup apps, remote backups are frustrating unless it's a local ethernet connection within a LAN/MAN.  WAN, is a different story.  One dropped packet will kill the job and you have to start all over.

[geva]

I should certainly have clarified an important point... the backups are not being done over a WAN, they are being done over a dedicated gigabit Ethernet backup network to a NAS-based B2D folder.  The NAS is then mirroring the B2D folder contents off-site using RSync.  So really what is being sent over the WAN is modified/added BKF (?) files.

I looked at deduplication and it seems that it would have been a great solution, however the ex-IT guy (read accountant) setup a brand new server with an old 32-bit version of Win2k3 SBS.... and dedupe requires 64-bit for the media server.

As for getting a full backup done between COB Friday and Monday morning.... between the system, user files, and Exchange, the total backup size would be somewhere around 100GB.  This amount of data would take weeks to get off-site over the Internet connection!

I have read elsewhere that differential and incremental should not be mixed.  I certainly do not have a problem with that.  What I'm looking for is a solution, and I can hopefully apply best practices along the way!

A concern that I have about FULL + Incrementals is that it will be a long time between full backups and I don't want to run into problems with having too many incremental backups.  For example files that were deleted 2 months ago being brought back in a restore.

As for the SEPM database backup.. the file is SEM5.db - aka the Symantec Embedded database which Symantec "recommends" over SQL.  Not sure why, but this is why I don't use SQL.  It is being backed up weekly using the SEPM maintenance thingy.  As this backup location cannot be changed, it drops a 3.5Gb goodie in the SEPM data folder. :(

I appreciate your thoughts/suggestions!  Keep them coming!