4 Replies Latest reply on Sep 29, 2010 10:05 AM by fjc

    ESRTII - mount disk without losing data?


      I have a few servers based on S3420GPLX boards, using the onboard ESRTII RAID controller.  Mirrored system drives, mirrored data, and a single RAID0 drive that the system backs up to (Windows 2008r2).


      If a server goes belly-up hardware wise, is there a way to take a physical disk to another server (using ESRTII as well), and mount that in a RAID0 fashion WITHOUT losing the data on the disk?  We'd like to do this to get critical data online ASAP.


      (Yes, I know we do perform backups to other network locations, but rather than wait while that's restored I'd like to just plug a drive in quickly).



        • 1. Re: ESRTII - mount disk without losing data?

          Yes you can. ESRT2 will read the RAID configuration stored on the hard drive and import it automatically.

          • 2. Re: ESRTII - mount disk without losing data?

            Hmm - we had a recent problem with a server wherein it is dropping dead (as if the power was cut) which we eventually tracked down to a bad motherboard.  This system had two mirrored drives as a virtual disk (C:), two mirrored drives as another virtual disk (E:), and two individual RAID0 virtual drives (F: and G:).  As part of troubleshooting, we disconnected all but the two mirrored system drives.  Later, when we plugged those other drives in and booted up the system, all it saw was two drives as a virtual disk (the system C: partition), and four "good, unconfigured" drives.  All the documentation I could find seemed to state that if I created a virtual disk out of any of them, all data on the drive would be lost.


            I carried one of the mirrored drives that made up E: to another non-RAID system and connected it via SATA and was able to read the data just fine.


            Should ESRT2 have just read the disk configs on the original server, instead of displaying them as "good, unconfigured"?  Perhaps this was part of our hardware failure...

            • 3. Re: ESRTII - mount disk without losing data?

              if the drive state is "good, unconfigured" it means the RAID configuration on the drive is not recognized.


              Good news is that since you're doing RAID 1 and single-drive RAID 0 only, you can still read and backup the data by connecting it to a non-RAID SATA port. Once you have the data backuped, connect them back to ESRT2 and create virtual drive using original settings, WITHOUT initializing the new VD. Most likely your data will be still there, but there could be inconsistency on RAID 1 VD so you may want to do a consistency check.

              • 4. Re: ESRTII - mount disk without losing data?

                Thanks for the information - I'll do some testing to make sure I have this nailed down.