Thursday 28 April 2011

DPM 2010 - "Replica is Inconsistent" on 2008 Servers for Statem State

It would be fair to say DPM is proving to be far better than Backup Exec on most things, but occasionally there are some short sighted decisions or stupid issues that could have been better handled.

One small example is where you find System State and Bare Metal Recovery Replicas keep becoming inconsistent on a Windows 2008 system that's being backed up with DPM 2010.

The fix is pretty simple. On the 2008 server you're backing up, go to "Server Manager", load features, choose "Add Feature" and ensure "Windows Server Backup" is an allowed feature (this won't need a reboot).

Given DPM seems to check loads of other pre-requisites you'd expect it would either alert you to this at install time, or just enable it as part of the install (even if there was an option which said "If Windows Server Backup features are not enabled on the source for protection, enable it automatically" or something.

A silly oversight and one that just takes a tiny bit of the sparkle of clueful implementation away I think.

Wednesday 27 April 2011

DPM - File Restores in Seconds, not minutes

As part of our deployment of Data Protection Manager (DPM) 2010, we decided we wanted to do as much restore testing as we could. So having contacted our usual customers who help us test and prove anything (call it a focus group if you want), we asked them all to delete random sets of files from the various servers we're backing up using DPM for them.

Obviously we asked them to make sure the files were not critical or important (just in case, safety first naturally!) - and then just tell us what files they wanted back. The theory being we should be able to do this without knowing in advance whats being deleted (ensuring nobody here could take extra backups or look out for anything etc).

Guess what, it worked... first time, and it is very fast. By comparison to Backup Exec, which took a minimum of 3-4 minutes even for a single 100KB Word Document (because of the whole loading media nonsense...), it did the job quickly, very quickly.

Where Backup Exec is more flexible however is if you want to restore a random set of files from a single file in different folders - DPM doesn't appear to let you do this - so I'd have to select files in a single folder, run "Recover..." then repeat for each folder (well through the UI anyhow). However, given the restore takes literally a few seconds, I'm not sure we care too much - and in reality doing this is pretty rare - normally we want a whole folder or a group of files in a folder or similar, rather than completely random odd and sods files from across a server.

Tuesday 26 April 2011

Microsoft DPM - A breath of Fresh Air (almost!)

Having finally reached the end of our patience with Backup Exec and its never ending failures to simple requests, the terrible performance issues it suffers and all the other problems we hear about and witness every day, we decided to give Microsoft's Data Protection Manager a whirl.

There are a few important things to think about though if you are looking to switch, since Microsoft DPM is really only about Windows, SQL, Exchange and Sharepoint. If that's what you're running, and you're on 2003 SP-2 or 2008 and above, you should be fine. If you need other platforms and apps which Backup Exec supports you're probably out of luck using this.

Microsoft DPM is a very different product. One of the key differences is that it is truely snapshot based. Backup Exec still does far too much by using file by file methods - this has terrible scaling consequences.

It is mostly about Disk backup, whereas Backup Exec has a wider range of support for traditional tape backup. DPM can do it (it calls this "Long Term" Storage, and uses Disk for "Short Term" (you define what short/long term is...)

So in a nutshell (kind of) here's the story so far:

1) Installation of DPM failed because the install folder was "C:\!Software\DPM2010" whereas the installer ignored the existance of ! and tried to load "C:\Software\DPM2010" and couldn't find its own files. So we just put up with that and put DPM2010 in the c:\ folder root so we could get started.

2) Installation takes a while as it also rolls out SQL 2008 (you can get it to use an existing Database but we opted not to - and this is the recommended approach).

3) Take time to read the pre-req's and understand how DPM works. For example, make sure you have a huge volume on each DPM server (the best scenario) you have left unformatted so it can claim this for itself.

With those basics covered, the initial installation was completely succesful and our first DPM server appeared.

Monday 18 April 2011

Microsoft Data Protection Manager

So we've reached the point after many years where we want to reduce our use of Backup Exec. Mainly because it is stupidly expensive and just not reliable enough.

So we figured we'd give Microsoft Data Protection Manager a go. Full of optimism, we began the install. It failed at the first hurdle.

You see the software was in a folder "C:\!Software\DPMServer2010"

Except the installer decided that is actually "C:\Software\DPMServer2010"

So although ! is a perfectly valid File System Character, the DPM Installer failed.

Folder renamed and it worked.

It isn't a good start... this is the sort of stupidity Backup Exec had!