Hot-swap procedure for Dell PERC 6/i

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Hot-swap procedure for Dell PERC 6/i

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I'm using a Dell PERC 6/i in a non Dell server with WD SATA drives for home use which has been working fine, and just have a few questions I'm hoping someone can answer or me;

  1. I am looking to upgrade to a Lian Li PC-343B Aluminium Cube Case using Lian Li EX-H33 SATA Hot-Swap cages. I've read through the PERC 6/i manual, but can't seem to find anything detailing the exact procedure required for hot swapping drives. Can I just pull them out without doing anything once I have them in my hot swap cages? Or do I have to mark them as being offline or something first? I'm also assuming these hot swap cages will work fine with the PERC?
  2. Assuming that I can just pull drives in and out, am I able to configure the PERC to automatically set the new disk as a hot spare and start rebuilding?
  3. I'm also seriously considering upgrading to the Western Digital RE4-GP 2TB drives, however I am already using all 8 connectors on the PERC. I understand that the PERC 6/i is capable of online capacity expansion? How does this work exactly? Do I just replace each drive one by one, waiting for the rebuild each time? How is the extra storage addressed at the end of the expansion process?
  4. If I were using 8x Western Digital RE4-GP 2TB drives, what would the suggested RAID level be? I'm currently using RAID 6 across the board (priority on capacity and redundancy over performance), however this is mainly because I'm currently using desktop class SATA drives that are more prone to failure. Using Western Digital RE4-GP 2TB drives that have a high MTBF rating and are built for RAID, do you think it'd be safe to do a RAID level migration from RAID 6 to RAID 5 with the amount of drives I'll be using?

Sorry for the newbie questions, I just don't want to try these things without knowing exactly what I'm doing. Much appreciate any help/advice anyone can give.

 

Regards

Verified Answer
  • 1. As you're not using a Dell server (backplane) it's not possible to 'guarantee' anything, but you should be able to just pull a drive and plug in another.

    2. as you don't have a Dell server, you'll have to see how far LSI's software can get you as the Dell software (OpenManage Server Administrator) only wants to install on Dell Poweredge servers. For questions on that software, you may want to try www.lsi.com.

    3. the "online capacity expansion" means you can add drives to an existing raid 0 or raid 5 (no other raid types) and the raid set can grow to include the new drives. The only way to go over those 8 drives is with SAS port multipliers. I haven't really seen these in 'cable format' yet; they are usually integrated into a backplane so that the raid controller can use just 1 or 2 cables to connect to 4 or more drives.

    However, there was a post that supposedly you can swap all drives with larger ones (one at a time) and then use Dell's "reconfigure" option in OpenManage Server Administrator (which you cannot run as you don't have a Poweredge) and select to just grow the virtual disk. This option isn't available in the PERC bios, but maybe LSI's tools can do this.

    One large flag: to use a (virtual) disk over 2TB (2048GB), the disk has to be converted to GPT before you put the first partition on the disk. GPT is only supported with Linux with a 2.6.x kernel, or if you're using Microsoft OSes; Windows 2003 SP1 or later, or for Windows desktop OSes it's XP x64 or Vista and later. Another flag is that a regular computer can not boot to a GPT disk. So, if you want to grow to above 2TB for a virtual disk, you'll need a separate disk/set of disks for the boot disk.

    4. I would not go raid 5 with SATA drives, even if they are listed to have a high MTBF. If you want a bit more performance, maybe go raid 50 (and have a cold spare or hotspare), but raid 5 is a really bad idea with large and slow drives unless you're just putting scratch data (data you don't mind losing at all) on there.

    Member since 2003

All Replies
  • 1. As you're not using a Dell server (backplane) it's not possible to 'guarantee' anything, but you should be able to just pull a drive and plug in another.

    2. as you don't have a Dell server, you'll have to see how far LSI's software can get you as the Dell software (OpenManage Server Administrator) only wants to install on Dell Poweredge servers. For questions on that software, you may want to try www.lsi.com.

    3. the "online capacity expansion" means you can add drives to an existing raid 0 or raid 5 (no other raid types) and the raid set can grow to include the new drives. The only way to go over those 8 drives is with SAS port multipliers. I haven't really seen these in 'cable format' yet; they are usually integrated into a backplane so that the raid controller can use just 1 or 2 cables to connect to 4 or more drives.

    However, there was a post that supposedly you can swap all drives with larger ones (one at a time) and then use Dell's "reconfigure" option in OpenManage Server Administrator (which you cannot run as you don't have a Poweredge) and select to just grow the virtual disk. This option isn't available in the PERC bios, but maybe LSI's tools can do this.

    One large flag: to use a (virtual) disk over 2TB (2048GB), the disk has to be converted to GPT before you put the first partition on the disk. GPT is only supported with Linux with a 2.6.x kernel, or if you're using Microsoft OSes; Windows 2003 SP1 or later, or for Windows desktop OSes it's XP x64 or Vista and later. Another flag is that a regular computer can not boot to a GPT disk. So, if you want to grow to above 2TB for a virtual disk, you'll need a separate disk/set of disks for the boot disk.

    4. I would not go raid 5 with SATA drives, even if they are listed to have a high MTBF. If you want a bit more performance, maybe go raid 50 (and have a cold spare or hotspare), but raid 5 is a really bad idea with large and slow drives unless you're just putting scratch data (data you don't mind losing at all) on there.

    Member since 2003

  • Thanks for the reply! I've often thought I should just get a second hand Dell server off Ebay or something so I could take advantage of OpenManage, but just not sure what I am getting myself in for exactly. A lot of money for me if I get it wrong. Have read of things like people buying a Dell server with PERC controllers thinking they have RAID only to find out they need a RAID key or some such to get RAID functionality to work. I just don't have the experience with Dell hardware to know the pitfalls.

    Having said that I'd love to get my hands on something like a PowerEdge 2800/2900 Tower, like this one for instance. If I were to buy something like this instead of buying generic PC hardware would I be able to transfer/swap out my PERC 6/i with whatever PERC card is in there? Also, are there any issues with using SATA drives in a Dell HDD cage? Anything else I should look out for? Being a home server, how noisy do these things get? Again, I appreciate any help.

  • A 2900 can do SATA drives just fine. You'd need the drive carriers, which Dell doesn't sell separately, but Ebay can sometimes yield some.

     

    A 2800 only does SCSI, so I'd avoid that one.

     

    The raid key stuff is only for older SCSI based onboard raid controllers. The raid key would turn the SCSI card that is built into the motherboard into a raid controller. With the PERC5 and PERC6 PCIe cards this is irrelevant.

    Member since 2003

  • PowerEdge 2800 uses PERC4, which is a SCSI controller, this is not compatible with the SATA drives you have.  Avoid 18xx or 28xx or x8xx, those use SCSI drives, or any older model (i.e.: x7xx).  The x9xx (i.e.: 2900, 1950, etc . . .) use SAS/SATA drives, and the newer models Txxx also uses SAS/SATA hard drives.

    The PowerEdge 2900 on the link has a PERC5 controller and you cannot migrate RAID volumes from a PERC 6 to a PERC 5, you can only go from the 5 to the 6.  The hard drives are compatible on 5 and 6 but, the RAID configuration can only go one way (5 --> 6).

    There is no RAID key for PERC5 or 6; I think that was the case for some PERC4's only.

  • Thanks so much for the replies again! So if the server is already fully populated with drive carriers, then I should be ok? That is there is only one type of drive carrier that take both SAS and SATA?

    Another big consideration for me is noise and heat dissipation. I don't have air con making summers quite stressful on 24/7 servers, which is one of the main drivers for me to look at upgrading to a Lian Li case in the first place. How resilient is the 2900 in less than optimal temperature conditions? And also, what is the noise rating as my study also doubles as a guest room?

  • The 2900 won't be all that quiet, but it should be fairly robust for higher than optimal temperatures. In the online manual you can probably find the operating temperature limits. At higher temps it'll run the fans faster to get the cooling it needs.

     

    As for the drive carriers, for the (Poweredge) servers, the carriers are indeed the same for SAS and SATA (for the MD-series systems SATA drives need an interposer board).

    Member since 2003