Linux LVM - Is It Ready for Prime Time?

Deagol asks: "I'd like to replace our aging IBM server with a commodity solution (Linux, 3Ware cards, and lots of IDE drives). The main reason is price (the cost of 5 36GB SCSI disks for this sucker -- one of which died today -- could pay for the replacement server with 2TB of usable space after RAID-5. Being a huge fan of AIX's LVM,I've recently been playing with the Linux version of LVM. It's got all the right features (and even the ability to shrink logical volumes, a feature which AIX 4.3.3 doesn't have!), though the commands aren't as polished as the AIX counterparts. The big question for me is, will it stand up and be stable under heavy load, like the IBM does? Is anyone running Linux LVM on a 1TB+, 24/7 production machine?"

Comments

Hot Swapping?

[oh]

I'm not going to buy into the IBM LVM vs Linux Software Raid debate, but no one has mentioned something thatâ(TM)s just as important. One of the big advantaged with a good SCSI enclosure is the ability to pull and pop drives in and out without powering down.

With good hardware, you can walk up to a running machine and replace the failed drive then and there. Hopefully your 144Gb raid-5 array has been fully rebuilt by the time you come back from lunch. If you don't have hot-swap hardware, you have to schedule downtime, come back later that night, shut it down, pull the drive and pop in a new one. And hope everything powers up OK, cos if the power supply stuffs up at that time of night and you don't have a (good) support contract you are going to have a lot of fun getting everything going again before the rest of the office shows up for work.

I know you can get hot-swap IDE hardware these days, but I've never used them. I suspect hot-swap IDE drives are not that much cheaper then SCSI, but I could be wrong.

One last little bit of advice, try including a hot spare in your array. Its nice to come in in the morning and read an email saying that a hard drive failed last night, and the array was automatically re-built using the spare before start of business. If you are going to go with non hot-swap hardware, Iâ(TM)d say this is a must. Running raid-5 in degraded mode is no fun.