Need Backup Strategy, Win2k8R2 Hyper-V Host and its 4 VMs.

Nice new big Dell T610, loaded, 4CPUs, 24GB Ram.  Internal Raid 5, total HD space 1.2 TB.
   4 VMs, 250 GB each, all running Win2k8R2 64-bit.

We need to adobt a backup strategy.  We're a small business, spent most of budget on the big box itself.  

What we've looked at so far:

1) "Windows Server Backup",  from the host, Full,  Daily, 4am.  VSS registry tweaks completed.   The target hardware is a simple dedicated external 2TB USB 2.0 Western Digital.    Problem:  Day 1 took nearly 9 hours to complete the backup.  Day 2 took 7 hours.  We can't subject the server to this everyday.   Are the long hours due to the relatively slow USB external HD or maybe because WinSerBk is doing a full backup of entire VM files everytime?

I was hoping that day 2 would be faster, maybe some incremental backup occurring, but now I'm thinking that the incremental backups are not possible with the host's VM files since as a file they change constantly and VSS probably timestamps file files too.  I guess copying 1TB+ everynight would take some time.    

I thought about only doing the WinSerBk every few nights instead of every night, but the WinSerBk settings only seem to allow for Daily at the longest, not every few days or eveen once a week.

2)  MS Data Protection Manager.  We have not actually tried this yet.  We've been told that this requres a pretty heftly hardware investment for server PC and at least the same amt of disk space 1.2TB, ie like a mirrored server same as our one $$ big one.

Any ideas and hints would be appreciated.   500 points.   Thanks.

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Svet PaperovIT ManagerCommented:
First, you say that you have 4x VM with 250GB each. This is a lot of data to process. Each backup solution that uses VSS will take the same amount of time no matter if it full or incremental backup.

I have almost the same setup as you - 2 servers with 10 VM total. I did a lot of tests, spoke to MS guys (from Dell) and read plenty of blogs before put all that in the production environment. For me the Windows Backup combined with some wbadmin scripts works perfectly. You just need to decide on your strategy.

However, may be you should consider the size of your VMs. When you say that each of them is 250GB I presume you are using fixed size virtual disks. There is no need for that. With Hyper-V in WS2008 R2 there is no difference in the output between the dynamically expanding disks and the fixed disks. You can easily convert them back to fixed if see some impact latter, but most important - keep them smaller - that is the beauty of VHD - we can expand them you we need - and in your guest OS, since they are also WS2008 you could also expand the logical partitions.

I hope this helps
Run the Windows backup from the host, once, to have base images. After that, use the built in Windows Back-up from each of the VMs. That way they will only back up what you designate as important instead of trying to copy the complete VM.
Yes, USB is slow, good for bursts of data, not continuous data transfers. If you want to continue in this fashion, get a esata connection and fast hdd to write to. Will cut your backup window down.

1st, decide what your goals are. How much downtime can you afford? How critical is the data?

Then let the requirements the business determines drive the solution. Think about getting the data offsite, at least the critical information.
JReamAuthor Commented:
I'll reduce the size of the fixed VHD files to something more realistic, such as 20GB, then see how long the backup takes.  Thanks.
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