Dell server PE 2950 replace hot swap drives

[ameyUK]

Hi guys,

We have a dell server pe 2950 thats our main file server. All the slots are in use and we have run out of disk space.. the options we have are
1.
Remove all drives, install bigger capacity drivers and recover all data to server..
2. hot swap drives
remove drives one by one replace with new drive and let the raid do its job built the new drive..

the problem with option 2 i havnt done this before I dont know how to go abt this.. any help on how to start will be really helpfull and will appreciate any help pls

thank you..

 

[rclarke250]

It will take a long time, swapping out 1 drive at a time and letting the raid rebuild each time, You should have a backup already. It would be faster and safer to backup, pull all the drives, but keep them numbered and in a safe place, install all the new larger drives, and lay the array back down from the back up. Also if something goes wrong, you have your original drives, and array to pop in till you get the kinks worked out.

 

[FaiTHLeSS]

You could add a DAS to the server allowing for better expansion

 

[ameyUK]

thank you guys, i was thinking of downtime.. when you install the new larger drives you still need to rebuild the array? .. because the back up of the array will have a different array size and partition..

DAS is it a big investment?

 

[rclarke250]

DAS is Direct Attached Storage, and it is basically a frame with power supplies,controller cards,and hot swap hard drive bays. Depending on the controller cards,and drives, it can get pretty expensive. If you swap a drive to a larger drive it will rebuild the array, each time that is done. After that, there is still some work to be done, as the array will not have given you access to the extra space, you need to go into the array management and resize the array. The easier way to do it, is to schedule downtime, make sure you have a viable backup, and install all the new drives, create the array for the new size, and then restore from the backup.

 

[ameyUK]

thank you rclarke250...

 

[ameyUK]

rclarke250 i got another question, if i remove all the drives and install all new drives and let the raid controller built raid on the new drives, followed by creating array for the new size.. then I install the OS on the new drives and recover the files from backup.. are these right steps?..

and

rebuilding the array on to a new disk how long would it take?

 

[rclarke250]

How are you doing the backup? Tape drive? tape library? How big is the existing array, and how big is the new array? which version of OS? scsi, iscsi,sata,fibre, what is the backbone to the backup?

There is no way I could answer that question. I've seen a new raid 5 system on a p5 aix machine take a little over an hour to restore from a makesysb (make system backup) tape. which is a bootable system and can restore the array in one shot. To a 10 node raid 50 with 1.7 Tb array on scsi take over 50 hours.

If your backup system is not bootable, then you would have to lay the OS down on the fresh array, which will take a couple of hours, install needed drivers.

Install the backup software if it is something other than windows backup, than do the restore. You could divide the time up, by creating the array on the new drives, and installing the OS. than at a different time doing the restore if it is a lot of data, or a slower tape system. after the os is on the array, just turn off the server, and put the old drives back in, till you are ready to do the restore if time is an issue.

 

[ameyUK]

hi rclarke250,

thank you for your help.. we have a tape drive and its iscsi.. the tape drive is connected directly to a symantec backupexec server .. am not sure if it bootable i need to check on that.. if it is then we can restore the data and os in one go.. and then extent the array..

thank again

 

[technome]

What size s the original array?


........................................
Chernobyl disaster..a must see pictorial

http://www.kiddofspeed.com/default.htm

 

[ameyUK]

one Virtual Disk 0
layout raid 5
size: 696.75

 

[technome]

Another method...
Get a SATA drive, attach to SATA interface. Clone the original array to it, remove old array drives, setup new array, then reverse clone from the SATA drive to the new array. This is the safest/fastest method, and you have the original array intact. If you use this method document the original array as to the slots and the drives as they are removed.

........................................
Chernobyl disaster..a must see pictorial

http://www.kiddofspeed.com/default.htm

 

[ameyUK]

thank technome,

So if I

1. Clone the array
2. Backup the server (full including OS, make it bootable)
3. Change new disks
4. Reverse the clone
5. Restore the backup

should the above steps do it?

my question is:

how can I clone the array, do i have use a cloning software (symantec or acronis) or can I use openmanage.. I had a quick look in openmanage but there is no options to administer array's on the server..

Also we use backup exec 12.5 am not sure if we can make it bootable.. we use a tape drive..i need to research if i can restore backup from boot up. thank you

 

[ameyUK]

--------- add on ----------

1. Can I just clone array and OS using Ghost?
2. Can use my tape drive to clone data?

If I can do above then

Once I restore the array and OS, I can use diskpart to extend the partition. then just restore the data

 

[technome]

2. Backup the server (full including OS, make it bootable)"
To have a tape which does a bootable restore requires software and tape unit specifically modified to make a tape restore bootable(expensive).

http://h18000.www1.hp.com/products/storageworks/drs/index.html

Openmanager has a disk manager module, reinstall to enable it.
I have used Acronis and Ghost, but Acronis for the last 3 years. Ghost would be cheaper, as I have used older versions for cloning. There are other cheaper/free cloning softwares, but I have not used them.

If you have a cloned disk it is an exact copy, sector by sector of the original volume(s), so no backup or restore from tape is needed, once you reverse clone to the new array, the new array is functional, other then making sure the new array set to be the boot drive. Chkdsk should be done on the array before cloning as cloning/images do not do well with disk errors.

That said, a full tape backup should be done as a precaution against user errors.

........................................
Chernobyl disaster..a must see pictorial

http://www.kiddofspeed.com/default.htm

 

[technome]

Once I restore the array and OS, I can use diskpart to extend the partition."
The cloning software you choose to use should have the ability to expand the destination volume size to use the entire space on the new array, during the cloning process.

........................................
Chernobyl disaster..a must see pictorial

http://www.kiddofspeed.com/default.htm

 

[ameyUK]

thank you technome,

I am planning to buy external harddisk ITB to create the image (£90 cheaper option)..

hopefully the server will boot from usb..

Planning to use Symantec GhostCast server 8.0 I dont know if it has ablitity to expand destination volume size..

At the moment on the server we have three partitions

size of old disks: 680 GB

c: (OS), d: (data), u: (user)

the size of new disks 4 X 1TB..

my question is;

1. Will I be able to just increase the size of d: and u: when restoring the image
2. If the cloning software Symantec GhostCast 8.0 doesnt have option to extent the volume size can i use diskpart?

just to recap so i dont mess anything:

1. Image the server to a external harddrive
2. Backup the server.
3. Remove old drives
4. Add new 1TB drives
5. Boot from external harddrive
6. Restore image
7. If option not available to extention volume size, use disk part..

am i missing anything..

thanks again...

 

[technome]

"c: (OS), d: (data), u: (user)

the size of new disks 4 X 1TB.."

Your into GPT disks, so read the link carefully. There is a 2tb volume raid adapter limit as to the boot drive.

http://www.microsoft.com/whdc/device/storage/gpt_faq.mspx

"2. If the cloning software Symantec GhostCast 8.0 doesn't have option to extent the volume size can i use diskpart?"
diskpart has limitations as to the boot partition, so google it. Ghost can expand to the size of the new array, but I have no idea if it works with GPT.






........................................
Chernobyl disaster..a must see pictorial

http://www.kiddofspeed.com/default.htm