Database server/RAID 1 partitioning question

[Mojo2776]

Hey gang, I'm relatively new to Linux, but the linux sysadmin job has basically been dropped into my lap. So here's my situation...

I'm building a new database server on a Dell Poweredge 6850 w/ 16gb ram.. I plan to install the OS (RHEL 4 AS) on the 67 gb mirror drives, and the database will be on the 2 tb RAID 5 array. My main question is, where should the swap partition be located... on the mirror or on the array?

[pewterdragn]

I'd vote for the mirror. Most of your IO will be on the RAID5 array (especially if this DB is Oracle) so if you do need to swap you seperate your IO needs to different controllers. Plus, if for any reason you need to disconnect the array you don't lose the system swap or have to add new swap files. If this is a dedicated DB server you're mirror drives shouldn't get much IO so swap should be fine there.

Just make sure the swap partition is also mirrored. I've seen so many systems where the root partitions are RAID1 but swap is just SPANNED across the disks its sad. You lose one of the disks with the swap and you can lose your applications or degrade the system depending on what had swapped on the failed disk.