IBM xseries 336

[asmith1972]

Hi We have a number of IBM x336 series servers. Now all these boxes currently are running Win2003 but only have 1 disk installed in them. What we would like to do is install a second disk and configure a hardware mirroring. Now does anyone know if I can just buy a extra disk plug this in and then mirror the 2 disks WITHOUT loosing any data. Or is it a complete rebuild job?

Cheers

 

[Jemimus]

Going over the documentation briefly, it would appear to be a rebuild.. or rather resync job.. so deleting all previous data.

However... we will give this a try for you tomorrow, we have 9 336 servers lying here for us to play with for the time being, and it so happens we where gonna unpack the last two tomorrow.

 

[scsiraid]

Can I assume that you are using the LSI Mirroring capability of the 336 and there is not ServeRAID 6i plugged in? If so... you can insert a second drive and turn on mirroring and it will rebuild without lost data. The easiest way is to use the LSI BIOS and select mirroring properties... set the current drive to primary and the new drive secondary and the initial sync will start. Let the OS boot and the rebuild will speed up.

 

[bonsky]

x336 dont need any raid adapter for it has built in RAID o and 1 capabilities. if you are going to rebuilt a configured disk, it will definitely wiped out all your existing data. Reason being is it will rebuilt the parity kinda for each sector. of the disk to work with specific RAID config. Even if you use as LSI to do primary or seconday, it will recreate everything to be in one raid array.
thanks!

 

[scsiraid]

I have never lost data in doing an 'after install' mirror on an NTFS filesystem. Data loss is possible IF the partition extends to near the absolute end of the drive (where the LSI solution wants to write its metadata) but it usually doesnt. Parity is not involved in RAID 1... only RAID 5. x336 doesnt have native RAID 0 capability, only RAID 1.

 

[rclarke250]

The x336 also supports 1E raid native. Parity is not just a product of raid 5, it is also used in raid 3. And it does support raid 0 native...

 

[scsiraid]

Where are you seeing a claim of RAID 0 support on LSI subsystems? The LSI 1020/30 requires a different FW load to support RAID 0 as there is insufficient memory space internal to the part to allow both striping and mirroring in the same image. See page 2 of the following PDF

ftp://ftp.software.ibm.com/common/ssi/rep_sp/n/XSD00361USEN/XSD00361USEN.PDF

You can get RAID 0 with an optional ServeRAID card though.

As to RAID 1E, this requires a minimum of 3 drives which the x336 isnt capable of... so even though the code allows it, it isnt configurable on an x336 since it has only 2 drives.

If you want to be picky... RAID 4 also uses parity.. but ServeRAID doesnt support that either. RAID 5E and 5EE also uses parity. I was trying to be generic.

 

[scsiraid]

One correction... RAID 1E is possible in the 4 2.5" drive model but not in the 3.5" (most popular) model.