Linux: Advice on RAID'ing!

feenster99 · 30 Aug 2006 at 21:09

Hi all,
From my previous post about a Backup Distro, I have settled with Fedora Core 5 (as I have some experience with FC3 so know my way around a little). I have it up and running sweet on an 80GB IDE drive.

I have a Promise TX2300 RAID SATA card with 2 320GB Seagate drives plugged into it. Now, I know the Promise card is "Fake Raid" - I have already setup the RAID 1 mirroring using it's BIOS, but FC5 won't see the drives at all.

Can/Should I just delete the array using the Promise BIOS, plug them into the card as simple SATA drives (in JBOD setup), then use this EVMS that I keep hearing about to put them into RAID 1? If I do that, should FC5 pick them up as new drives and let me format them, or do I need to do that bit first (if so, how!?!)

Many thanks,
Matt

NickK · 30 Aug 2006 at 22:20

feenster99 said:
Hi all,
From my previous post about a Backup Distro, I have settled with Fedora Core 5 (as I have some experience with FC3 so know my way around a little). I have it up and running sweet on an 80GB IDE drive.

I have a Promise TX2300 RAID SATA card with 2 320GB Seagate drives plugged into it. Now, I know the Promise card is "Fake Raid" - I have already setup the RAID 1 mirroring using it's BIOS, but FC5 won't see the drives at all.

Can/Should I just delete the array using the Promise BIOS, plug them into the card as simple SATA drives (in JBOD setup), then use this EVMS that I keep hearing about to put them into RAID 1? If I do that, should FC5 pick them up as new drives and let me format them, or do I need to do that bit first (if so, how!?!)

Many thanks,
Matt

If you set up RAID in the BIOS then all the BIOS reports to linux is the pseudo drive which is the RAID array. The RAID 1 is provided by the BIOS rather than the operating system.

To software raid linux just use standard non-RAIDed SATA connected drives.

feenster99 · 30 Aug 2006 at 22:26

NickK said:
If you set up RAID in the BIOS then all the BIOS reports to linux is the pseudo drive which is the RAID array. The RAID 1 is provided by the BIOS rather than the operating system.

To software raid linux just use standard non-RAIDed SATA connected drives.

But can I connect them through the Promise RAID card but just leave them in JBOD (the default)? If not, do you think the Promise card might need a driver for FC5 to get it to show the pseudo drive so I can mount it? If so, I may be a bit stuck as Promise don't have a new enough driver. I can't see sight nor sound of the pseudo drive in Fedora.

I think having Linux do the RAID would probably be better anyway, as it would be easier to monitor (Promise don't offer a Linux monitoring tool I don't think).

Matt

NickK · 30 Aug 2006 at 22:34

I've not used the Promise controller. However I would just leave the as JBOD and treat the card as a basic dumb SATA controller and then run linux with evms.

For Linux raiding, "RAID" on the controller card isn't required.

feenster99 · 30 Aug 2006 at 22:39

Just what I needed to know, thanks. Just need to look into EVMS now. Does it install into FC5 ok do you know? I've spotted packages for Debian etc, but no Fedora 5

Matt

NickK · 30 Aug 2006 at 23:05

feenster99 said:
Just what I needed to know, thanks. Just need to look into EVMS now. Does it install into FC5 ok do you know? I've spotted packages for Debian etc, but no Fedora 5

Matt

Linux itself supports the raiding (0-6 levels are supported) - either built into the kernel or as modules.

EVMS doesn't do the raiding par-say but provides much better volume management options than the existing volume managers. EVMS was originally written by IBM for their enterprise platforms IIRC.

feenster99 · 31 Aug 2006 at 07:38

Thanks Nick. I've noticed the Logical Volume Manager in FC5 is quite weedy, so i'll give EVMS a shot.

Thanks for all your help.

Matt