I'm building an Ubuntu 9.10 home server to essentially backup all my PCs to, serve media, and store other large data (I record music and film). Here's what I have as far as storage goes:

• 4GB CompactFlash: for OS
• 2x 500GB WD drives: intended for RAID-1 for backup (which I will in turn back to external drive on a weekly basis)
• 3x TB Hitachi drives: intended for RAID-5 for media and storage

Both RAIDs will be software-driven. Now, a few questions:

1. From what I've read, I can benefit from using LVM on top of the RAID. Is this true, and besides the complexity and potential difficulties in recovery in case of disaster, is there a downside to LVM?
2. Would I benefit at all from using smaller logical volumes on the RAID-5, or should I just make one at the full size of the drive?
3. Also from what I've read, it seems that XFS may be the best filesystem to use, from a stability and performance standpoint. Should I go that route, then? I suppose that if it IS beneficial to have multiple smaller logical volumes, then there may come a point that I need to shrink and grow these logical volumes, and if that's the case, it appears XFS is out of the question. What's the runner-up; Reiser?
4. I currently have /swap and /home partitions on the CF card. I'd at the very least like to remove the /swap partition and just create a swap file on the RAID-5. Should I move my /home partition to the RAID-5 as well?

Hope I'm not askin too much here! Thanks guys.

Can't answer all the questions, but here is my thoughts.

1. Yes, you can use LVM on top of the RAID. At my work we do it all the time. One upside is that we start off with logical volumes that are bigger than what we need, but not using the full disk. Then, later, if one volume grows faster than we expected, we simply re-size it with the unused space.

2. Don't really know. The original reason for the small volumes was that one drive could not hold everything. Admins had to separate the storage into volumes which translated directly into physical disks. If a physical disk died, you only had to restore/rebuild the disk that died rather than your whole system. With bigger and bigger drives, as well as RAID for protection if one disk dies, this is no longer the case. Some people feel that it is fine to make one big drive and not worry about mount points or size. Others continue to use multiple volumes for personal organization. Some create new volumes specifically for songs and videos rather than leave them in /home so that 1) they can be shared, and 2) they are logically separate from their documents. I can't really tell you if your performance will improve or degrade with lots of small volumes or one big volume.

3) Can't answer this one either. We mostly use ext2 (for boot partitions) and ext3 (for everything else). In conjunction with LVM, it makes volumes easier to re-size and have never had a problem with them.

4) A personal opinion. It depends on what you will have in your /home partition. If it were me (based on what I typically use), I would move the /home to the raid. I would leave /boot and /usr on the CF card, and create the swap partition as well as /home and /usr/local on the RAID.