Converting a LVM volume to RAID 5
 

I'm thinking of converting my LVM volume of 1,5.TB to RAID 5 (software) and have some questions:

- Does every disk have to be the same size? (If not, will you "lose" space?)

- Any ideas on how to approach this? (I don't have any drives to temporary move my data to :( )
(currently using about 70% of the disk space)

- What is the preferred file system on RAID (currently using ext3)

- Any advantages with running LVM over RAID 5?

- How easy is it to add a new disk to a RAID 5 volume?

- What will happen to the RAID volume if i decide to reinstall my distro or f eks change it?

- Anything else i should now?

resources i have been reading up on:
http://www.midhgard.it/docs/lvm/html/index.html
http://evms.sourceforge.net/

(posted in software category because it's software raid :p)

in order...

- yes

- temporary drives... sorry. you can build a degraded array in theory, and keep data on that spare drive until you are done creating raid. but then you still have to shrink the lvm and such, equally tricky if you're not used to it.

- no preferred one really, depends how big the filesystem is really, not what it's running on.

- well they are different. lvm is more flexible, but provides no resilience at all.

- you don't. raid 5 stripes parity across devices, every 3rd block on three drives, every 5th on 5 etc... can't just nail another one on.

- nothing really, should be picked up fine.

- probably find a better solution than this..!

It seems that evms are able to handle RAID 5 expanding, doing a test in vmware with some non critical data to see if everything works out.

http://img230.imageshack.us/img230/8843/raidtesttv2.jpg