Tuesday 24 March 2009

SBS 2008 – Using SBS Backup to Expand an Array and Partition

When we set up our SBS 2008 installs, we use a RAID 1+0 configuration with three partitions on the RAID array.

We do this because of the extra throughput we get for both reads and writes. RAID 5 takes a pretty good performance hit on writes, while reads are similar to a RAID 0 stripe.

Our partitioning is done as follows:

  • System C: 100GB
  • Swap File S: 25GB (2.5 * RAM)
  • Data Partition L: GB Balance

Now, since we do keep the Exchange databases on the system partition, the size of the organization is an important consideration when it comes to the size of it.

For some RAID controllers, there is the ability to add disks to the array on the fly. From there, we can open the Disk Manager and Extend the last partition on that array.

To resize, move, or modify any of the other partitions with the newly acquired space will require a third party utility that can work with server partitions.

In the case where the RAID array cannot be expanded on the fly, we have the built-in SBS backup to use as an intermediary. The catch is the need to delete the existing array and create a newer and larger one in the RAID controller’s BIOS.

The whole process is actually quite simple and will take a few hours depending on the size of the backup being used.

  1. We take a backup just prior to downing the server.
  2. Shut down the server.
  3. Insert the new drives.
  4. Reconfigure the RAID array by deleting the existing one and creating a new one incorporating the new disks.
  5. Boot from SBS 2008 DVD 1.
  6. Click the Repair link.
  7. Restore my PC.
  8. Choose the backup just made for the restore.
  9. Make sure to load the RAID drivers just in case during the backup restoration steps.
  10. Run the restore.
  11. Go have coffee, tea, or take on another short project.

The restore process is set to automatically reboot into the newly restored OS once it finishes.

From there, head into the Disk Manager in the SBS Native Tools Management Console and extend that Data partition.

The new SBS 2008 Backup is phenomenal. The more we experiment with its abilities, the more we grow in confidence using it as our default backup program.

Philip Elder
MPECS Inc.
Microsoft Small Business Specialists
Co-Author: SBS 2008 Blueprint Book

*All Mac on SBS posts will not be written on a Mac until we replace our now missing iMac! (previous blog post)

Windows Live Writer

4 comments:

stryqx said...

I've been using RAID-10 for a long time for the very same reasons. The only time I use RAID-5 is when random read performance is critical. I have been looking at RAID-6 recently given the better redundancy and the ability to add more spindles.

You might want to rethink your pagefile sizing. A percentage of RAM isn't necessarily wise. The following two references are a good read in determining this:

http://blogs.technet.com/askperf/archive/2007/12/14/what-is-the-page-file-for-anyway.aspx
http://support.microsoft.com/default.aspx?scid=kb;EN-US;889654

I generally break up the data partition into two - a high volume write partition and a low volume write partition. This then allows me to set different Shadow Copy settings for the partitions, allowing a greater version history for the low volume write partition and minimising loss of versions in the rare occasions where all versions are lost due to the shadow copy area not being able to grow in time. It's not a substitute for backups, but deep version history has eliminated just about all restores from backup media.

Philip Elder Cluster MVP said...

Chris,

Excellent pointers and both are a good read!

I will rework our own server configuration settings as a result.

When it comes to restoring a deleted folder via VSC, what is your methodology?

Thanks for the comment,

Philip

stryqx said...

Glad you found the articles useful. The "Ask the Performance Team" blog is an outstanding blog, as is the "Ask the Active Directory Team" blog. A must-read for IT Pros managing Windows networks.

Restoring folders can be done either from a client or from the server. Both involve browsing to the UNC path using the Administrative share, going into the Previous Versions for the parent folder and viewing the folder contents, then copying the deleted folder back to the parent folder.

Anonymous said...

We have a Dell PE T410 SBS 2008 server with 2 sets of mirrored drives. 1 sata drive set has data on it and the other is a fast SAS set that has a mirrored pair of 136gb drives with 4 partitions on it preset by Dell in this order:

• 71mb hidden EISA configuration Dell partition
• F: 3gb Company primary partition with some Dell files on it
• C: 60gb primary partition with OS
• E: 73gb logical partition with Exchange and WSUS

The 60gb C: partition is now too small for the OS (yes I know Dell and Microsoft sizes recommended were too small).

I have now replaced the original 136gb drives in the raid with a 278gb ones by replacing one hard drive at a time into the raid and remirroring. However SBS still sees this as a 136gb drive not as 278gb one.

To fix this I believe I have to go into the raid bios (SAS 6/iR controller) at boot up delete the 136gb raid – rebuild the raid as 278gb so that SBS can see it all and then restore all the partitions from a USB backup.

However the native SBS 2008 backup does not see or backup the Dell hidden partition?
What exactly do the 71mb Dell hidden and the 3gb F: partitions do anyway?

I am wondering if therefore Windows SBS native backup and restore is the best way to do this as it doesn’t see the hidden Dell partition or is there a product that uses a boot CD and can do a cold/offline sector by sector backup and restore that would be better.
I had a really good experience of doing a cold/offline backup with Norton Ghost 2003 with an SBS 2000 server and restoring it but that was a while ago on a much older server. Would this still work or is there another more up to date product that can do this?

Any help much appreciated.
Phil Cooper