[ubuntu] Advice needed on fake-raid

[jinnantonnixx]

I've bought a HP MicroServer (good deal from Serversplus) and my intention is to use it as an XBMC multimedia server.

 

My planned configuration is this:

• OS on the supplied 250GB disk (Ubuntu minimal 64 bit, Openbox windows manager, XBMC server - simple and fast.)
  
• RAID 1 (mirror) on my two 2TB disks.
  
• 
  

 

Now, the Microserver has a fake-raid system, you can specify a RAID array in the BIOS, and it appears that Ubuntu can see this as a mapped device.

 

Which is best - a software RAID in Ubuntu? Or use the HP Fakeraid facility?

 

As I understand it, the raid system on the Microserver can rebuild an array before the OS starts when you install a new disk. But this is only from what I've read on forums and I can't confirm or try it.

 

Of course the software RAID is more transportable and not reliant on any hardware configuration should my machine go bang.

 

Thoughts?

Edited December 22, 2011 by jinnantonnixx

[morganw]

If you want to monitor the array and have the system send you an email when a drive fails then software RAID would be the only choice.

If you aren't confident with software RAID then the other way is easier to setup and replacing disks should be easier.

[glennda]

Personally software raid in that instance as you would be able to swap the hardware if it went down - you.could put it into another machine and reboot. Plus the fake raids tend to be a bit crappy.

 

My backup server which has 16 2tb drives in runs a ubutntu software raid raid and I've not had any problems with it.

[jinnantonnixx]

Agreed. Software Raid seems safer in this case. Thanks.

[SYNACK]

Linux is rubbish at handling fake raid due to lack of vendor driver support and plain incompatibility. If using linux go with native software RAID.

[dhicks]

If you want to monitor the array and have the system send you an email when a drive fails then software RAID would be the only choice.

 

Actually, Linux support for hardware RAID cards is better than you might think, you just need to find the right package to install to monitor your particular card. Most RAID cards are based on one of a certain limited number of chipsets, too, so there's probably a monitoring package out there for whatever RAID card you have installed.

 

For the situation above, though, I'd definatly stick with Linux software (MD) RAID. You won't get any performance improvement out of using a fake-RAID card - if anything, MD RAID is probably going to be better, especially if you can leave it a good chunk of RAM to use as a cache. As has been pointed out, MD RAID is much easier to recover - in fact, once you have a RAID array set up and plugged in it can be quite tricky to get rid of. I've just had a controller problem on an old server here, so I swapped the harddrives to a new controller card (jumbling up the order of the disks in the process, of course) re-installed Debian and on booting up the new OS install found the RAID array ready to go, complete with an assigned device number in /dev and all logical volumes present and mountable. If your main OS disk dies you can boot something like SystemRescueCD off CD which will automatically construct and mount any MD RAID arrays it finds without you having to do anything, so your data really should be very safe.