software raid 5 + LVM
i wanna redo my file server and use software raid 5 + LVM, but before i do that i want to ask few question. i have about 10 160gb PATA drives that i want to use. the setup is simplified by using those 10 PATA purely as storage since OS (slack 11) will be residing on 30gb pata drive with cd rom on one of the IDE channels on the mobo.
so now the motherboard has only 3 PCI slots and 1 free onboard IDE channel (the other one is taken by OS HD and CDROM - on one cable). to fit all 10 Storage HDs i'd need 10 IDE channels and to have 1 HD per channel i'd have to get 2 IDE PCI controllers with 4 IDE channels and then 1 2 channel IDE controller and then i will have one spare for future upgrade.
but then again will it be hard (read: will i have to rebuild raid) if i wanted to upgrade the 3rd 2chan IDE controller to 4 chan?
now lets get back to the software. since ill be building software raid i don't care if the ide controllers will have built in raid capabilities.
setting up the raid is fairly easy ill probably set up raid 5 with 8 drives set up for storage and 2 as spares. is spare in software raid unusable until another drive breaks and then it's used to mirror the bad drive? or will i be fine with one?
also since i want to have the ability to add drives in the future and expand the storage, and it's hard to do with the software raid without moving data around, i'd also want to put LVM on top of the RAID. now should raid be created first and then LVM or the other way around?
also will there be a problem if i decide to add disk to raid that has different size the the disks in the array. since it's software i shouldn't have any major problem right?
i believe the HDs are in ok conditions but should i test them before building the array 1 by 1 or would it be the same if i did the test after the array is created and when it finds the error it will point me to the faulty drive and allow me the replace it?
i will add some more questions and concerns to this thread. thank you for any input, which is highly appreciated.