How to restore a Small Business Server OS disk image to a new drive

kiwi_canuck
kiwi_canuck used Ask the Experts™
on
I have a Dell PowerEdge 2900 with PERC 5/i integrated disk controller, with SBS 2003.  Disk setup is
HDD1 - Mirror - OS C:\
HDD2 - Mirror - OS C:\
HDD3 - RAID5 - DATA D:\
HDD4 - RAID5 - DATA D:\
HDD5 - RAID5 - DATA D:\

I used Acronis to take an image of the OS volume.  Simulating an OS volume failure, I shutdown the server and removed both OS drives. I inserted 2 new blank drives and booted the server.   I pressed Ctrl-R to run the disk configuration utility and received the message that virtual disk 00 was missing.  I created and initialized a new virtual disk, then re-booted from an Acronis Rescue CD.  My data volume was now called C:   I created a primary partition on my new virtual disk, labeled E:.  At that point I got stuck at the Acronis message The trial version of ATISBS allows you to add a new hard disk from the OS only.  Please boot the OS and add a new hard disk.   I shut the server down , put the original drives back in, imported the foreign configuration and the server was back to normal.

I want to try this again tomorrow but have a few questions:
1)Where on the hard disk is the RAID configuration stored?
2)If I restore an image of the whole OS drive will it restore this configuration information?
3)During the process I was concerned that my data volume was called C.   Would it be better to take the data drives offline before booting to the Acronis rescue CD?
4)Should I create the mirror set first then restore the image as I attempted, or restore the image to one drive then create a mirror?
5)Is there any other tips that could improve my process?

Thanks,
Cliff
Comment
Watch Question

Do more with

Expert Office
EXPERT OFFICE® is a registered trademark of EXPERTS EXCHANGE®

Commented:
1) HDD1&2, its in the system partition.
2) Acronis® Universal Restore detects the hardware and installs drivers

    * The product detects the machine type and installs appropriate drivers for Hardware Abstraction Layer (HAL)
    * The product detects hard disk controllers (SCSI and IDE)
    * or
    * The product prompts you for driver locations

You may need a usb stick formatted as a floppy disk or a floppy disk with the perc drivers to access the hard drives.

3) Yes, you could try specifying in disk management the drive letter for the data drive.

4)Create the mirror set first then restore the image as you may inadvertently write over the image the other way. I am assuming hardware RAID?

5) If possible RAID-5 or better on the system partition.

Author

Commented:
j210277:  
1) So, to confirm, the hardware RAID 1 configuratuion data for HDD1&2 is stored on the system partion.  Where abouts?  In a file on C:?
2)  If Acronis does this work, do I need to bother setting up the RAID 1 configuration for the new disks via BIOS?
3)  I'll try that.  Have you tried it yourself?
4) Yes, hardware RAID.  OK.
5)  Wouldn't RAID1 be better than RAID5 on the ststem partition for reading speed and fault tolerance?
Thanks.
Commented:
1)I apologize didn't ask what RAID system you were using on the previous question I assumed it was software RAID the hardware RAID configuration is stored in BIOS, software RAID is stored in c:\windows, the perc drivers are kept in c:\windows\system32
2) The hardware RAID setup is OS independent, so no it will not restore the RAID configuration this is all housed in the BIOS.
3&4) You can either setup first or not either way will work, I have done this myself and have inadvertently written over the partition with the fresh image when setting up the hardware raid after installing it on one disk, that is why I suggest setting up the RAID-1 config first to eliminate further complexity in setting up RAID afterwards.
5) RAID-5 negates the need to have to spend time restoring the solution the way you are trying to do as you can just have a blank drive replacing the harddrive and restoring from the other 2 eliminating the need for restoring an image from acronis and all this other stuff it is slower then RAID-1 you are correct. Check out this article for more information about RAID http://en.wikipedia.org/wiki/RAID

Acronis in Gartner 2019 MQ for datacenter backup

It is an honor to be featured in Gartner 2019 Magic Quadrant for Datacenter Backup and Recovery Solutions. Gartner’s MQ sets a high standard and earning a place on their grid is a great affirmation that Acronis is delivering on our mission to protect all data, apps, and systems.

Author

Commented:
Thanks for the info.  

1) What you say sounds reasonable.  One thing still bothers me.  If hardware RAID configuration data is kept in the BIOS, why is it that the BIOS reports a foreign configuration view only after I insert a foreign disk?  The BIOS seems unaware of the foreign configuration without the disk being present.  It appears like the configuration data is stored on the disk.  I dont see where in the BIOS I can scroll through a database of configurations.    So is the config info really stored in BIOS?
 
5)  I am simulating both OS disks being faulty (like in a fire) for disaster recovery testing, so I need to be able to recover from the backup image.
Thanks.

Commented:
What hardware RAID solution are you using?

Commented:
Ignore last post.
Found it.

Commented:
RAID config for the PERC cards are stored in the RAID controller BIOS.
I believe the RAID controller recongnises the fact that the replacement disk you have inserted is not the same disk as the orginal and subsequently throws up the foreign disk configurator.
If you insert the original the RAID controller doesnt freak out becaus thats the disk it was expecting.

I use Poweredge 2900's with PERC cards but I use Symantec Backup Exec System Recovery Server for enterprise imaging.
Every PE box I have has BESR installed and it works great.
Done a number of DR's with the product.
If you're struggling with Acronis try the trial version of BESR.
I have one SBS server left running on PE 2900 which I did a DR test for the other day using BESR and it worked like a charm.

Author

Commented:
Hi Dextertronic.  Was hoping you would comment as I valued your input on my last post.
When I removed the two OS drives and put 2 clean drives the RAID controller gave the message "VD's are missing: 00.  If you proceed or load the config utility these VD's will be removed from the configuration.  If you want to use them later, they will have to be imported...."  I proceeded (presumeably clearing the configuration in the BIOS), and manually set up the 2 new drives as RAID1.  Later when I put the originals back in the BIOS reported the foreign configuration which I imported.  So are you thinking serveral versions of the configuration are stored in the BIOS against disk ID's or something?

Could I please also have your comments to my questions 3, 4, 5 at the very top?
Commented:
I would have thought that only one config was stored at a time but that it does track the disk id's so  if somethng new gets inserted you get prompted with the foreign disk dialog which allows you to set up a new config.
Good question, I'm going to check the manual on that one.
3) That would stop the your data volume being reallocated as "C". I havent used Acronis but it's not that different to BESR. There should be a utility in Acronis available at that point in the restore that allows you to work with volumes and assign drive letters etc
4) Creating the MIrror set while theres no data can be a lot faster. And if I was being paranoid I wouold suggest that it's safer. BUt the PERC cards are really good so I wouldn't be too worried about that aspect. My preference is create the mirror first.
5) I think you got most of the process nailed. I think it's a great oppurtunity to create a step by step document for this procedure. I write mine as if a non technical person had to do it(God forbid) but with Acronis\BESR bare metal restore it is actually possible. It's awesome that you're actually going through it as the vast majority of people don't even test their DR plan,

Author

Commented:
Thanks.  I look forward to hearing what your manual says on the RAID config location question.  Thanks for your other comments.

Commented:
http://support.dell.com/support/edocs/storage/RAID/PERC5/en/UG/HTML/chapterh.htm#wp1053724
As I read it only one configuration state can exist on the RAID controller at any one time.
The Foreign Configurations prompt can be a result of something as simple as removal of a physical hard disk.
Once you have performed the Foreign Configurations import or clear procedure that new configuration is written to flash memory on the controller and that is the new state.
WHat is interesting is that the Foreign Configuration View appears to assess the new disks as a whole and identify whether or not they can be imported as a functional virutal disk.
So if you took your two new ones out and put your two originals in, the card looks at the disks and decides it can import them as A RAID 1 Vitual Disk.
I'm going to try it out on a 2900 test machine this afternoon and see what happens.

Author

Commented:
Thanks for the link to the manual.   I look forward to hearing what happens in your test!

Author

Commented:
I am not sure if this helps but there is another bit of information that makes me think the RAID configuation is stored on the HDD somewhere.  Before I started, virtual disk 0 (VD0) was on disk group 0 (DG0), and VD1 was on DG1.  When I shutdown the server and replaced the OS drives the controller reported VD0 was missing as expected.   When I manually created a new VD with the 2 new physical disks I noted things had switched around:  VD1 was on DG0 and VD0 was DG1.  When I later put the original OS drives back in the foreign configuration showed VD0 on DG0 and VD1 on DG1 as orginal.  How could it do this unless that config was stored on the disk?
Commented:
It was stored on the disk and the RAID controller
A digital signature is written to the disk by the RAID controller which is read upon boot up.
If a different signature exists it lets you know and you get the option to import.
Just tried it on a 2900 and it did the same thing.
I spoke to a Dell tech today who confirmed it.
 

Author

Commented:
Interesting!  So what are the implications for imaging?  Is the RAID configuration captured by the disk image in any useful way?

Commented:
I've never had any problems with the imaging side of things.
I take images of volumes and restore them to different RAID types on different servers and they've never complained about foreign configurations.
Makes me wonder where the "digital signature" actually sits.
Maybe it's stored in some special part of the buffer or some other kind of flash memory.
 

Author

Commented:
I will install new physical disks, restore from an image and check what VD/GD configuration combination is reported.  

Author

Commented:
I will return to this soon.

Author

Commented:
Right, finally got back to this.  Thanks for your patience.

Virtual Disk 0 is on Disk Group 0, and VD1 is on DG1.  I used an Acronis Boot CD to take an image of my C: drive which I saved to my data volume.  I shutdown the server and removed the two OS drives.  I installed two new drives for the OS and booted the server.  I used CTRL-R to go into the RAID controller BIOS, and set up a new virtual disk using the 2 new physical drives.  Now VD0 is on DG1 and VD1 is on DG0, i.e., swapped around.   I restored the image to the new virtual disk.   This is where I was curious if the image had captured a drive ID signature that would change the VD/DG configuration back to original.  It didn't.  I ended up with VD0 is on DG1 and VD1 is on DG0, i.e., swapped around.

Just before I restored the image, Acronis recognized my Data volume as C:, and I was worried that restoring the image would try to create a C: drive when the data was already labelled C:.  But after restoring the image of the utility partition, C: and the MBR, the drive letters fixed themselves so all was good.

Server booted up like normal and is working great, and I have successfully tested restoring an image for Disaster Recovery purposes.

Commented:
In the BESR restore function they let you check a tick box for Restore Drive Signature.
Sounds like Acronis does it automatically.
It's a comforing thought to know that if something does go horribly wrong you're 100% sure that you can restore your server to new hardware with ease.
 

Author

Commented:
Actually, Acronis has a drive signature selection box too.  You can create a new signature or recover the signature from the image.  I cannot be sure what I selected.  Might try it again.

Author

Commented:
I find that Acronis allows me to recover the drive signature if I am restoring disks, but not if I restore volumes.  I used the restore volume option because I restored the OS 25 GB partition to a larger partition, so I didn't get the chance to see if restoring the original drive signature changed the VD/DG configuration.

Author

Commented:
In summary the answers to my questions are:
>1)Where on the hard disk is the RAID configuration stored?
It is stored on the disk and the RAID controller.  A digital signature is written to the disk by the RAID controller which is read upon boot up.

>2)If I restore an image of the whole OS drive will it restore this configuration information?
Don't know.  Possibly if the drive signature is restored, but I did not try that.

>3)During the process I was concerned that my data volume was called C.   Would it be better to take the data drives offline before booting to the >Acronis rescue CD?
During the restore process the drive letters were corrected (C: for OS and D: for data).  It was better to leave the data drives online because it was handy to backup the OS image to the data drives.

>4)Should I create the mirror set first then restore the image as I attempted, or restore the image to one drive then create a mirror?
Mirror first.

Do more with

Expert Office
Submit tech questions to Ask the Experts™ at any time to receive solutions, advice, and new ideas from leading industry professionals.

Start 7-Day Free Trial