-1

We are running our datacenter with one array of RAID 1 (with 2 x 2TB) on a HP XW6600 (CentOS 7).

We'd like to increase disk space and avoid as much as possible downtime while upgrading.

There are currently several solutions:

  1. Switch from RAID 1 to RAID 10. High risk of downtime (or even data loss) since we don't have any server expert in the firm. We don't prefer this solution much.

  2. Keep the current RAID 1 but swap the disk to larger volume. Low risk and less downtime. This seems possibly the one we choose but we waste 2 x 2TB old disks. So the 3rd one appears in the mind.

  3. Keep the current RAID 1 and install another new RAID 1. Is this possible with the current HP server?

The-Vinh VO
  • 121
  • 6

1 Answers1

1

The answer to this question is subjective to the hardware you have installed.

  1. Trying this is usually a recipe for disaster as changing raid configurations usually requires the raid to be initialized, which essentially wipes the disks. You can use tools to make a complete backup of the disk, and then restore the disk afterwards, but as you say you don't have any server experts, I'd avoid that.

  2. Simply swapping the drives doesn't work. You'll have to do one, let it rebuild the array (assuming no failures), then swap the second, let it rebuild the array (assuming no failures), then try expanding the array size. There is another potential issue too. Disks above 2TB need to be using GPT instead of MBR. If the disks are using MBR, then they need to be rebuilt using GPT. Changing MBR to GPT will result in the destruction of data. Read a quick blurb on GPT and MBR here. There are some tools that'll do the conversion between the two, but I've not had any experience, so I cannot make any recommendations.

  3. This depends on available hardware in the server. Looking at the specs found here, and some pictures I found, looks like there are only 2 bays available for 3.5" or 3 for 2.5", with additional front facing external bays of 2- 5.25" or 1- 3.5". Assuming you already have 2 drives, a CD/DVD drive, and a floppy drive, you may not even have space for additional drives (assuming 3.5" hard drives currently). That doesn't even count the RAID controller you potentially have available either. If you don't have available ports, or an expanded backplane for the drives (uncommon on work stations), you may not be able to attach the new drives.

Jon Angliss
  • 1,782
  • 10
  • 8
  • So it just cannot be done physically (or 1 & 3 are impossible). I will check the machine interior later. For now the disks must be rebuilt using GPT and, just want to be sure, can CentOS 7 boot normally with GPT disks? Because that machine is a bit old, I'm quite sure it is not running with UEFI. – The-Vinh VO Jan 22 '18 at 07:05