There's lots of information at http://dbasupport.com/oracle/resourc...Hardware/RAID/ about RAID configurations. Basically, RAID 1 is mirroring. For every disk, you have another disk.
Originally posted by mike73
Please help me understand about the the differences between raid 1 and 5 since I am not too clear about how this work.
RAID 5 uses what's called parity striping. With RAID 5, each write is spread out over all the physical disks along with parity information. If one of the disks is lost, you can continue at a diminished capacity. If you lose two disks, you're SOL.
From what I understand, when you have raid 5 and you have 5 physical disks, it will stripe to 1 big disk so if you write to the disk it will write randomly to one or two out of these 5 disks right ???
No, not quite. The writes go to all disks in the RAID volume.
Here is what we do in my company and I think it's not right ??? they have raid 5 and they only have one partition since they said no need to have many different partitions since i will write to different disks any way, it only cause overhead if we have more than one partition. Is that a true statement ???
You get no performance advantage by having multiple partitions on the same RAID volume.
So we have only one partition and they put datafiles and index files in one partition. Is that right ???
In the ideal world, I wouldn't do it like that. You are setting yourself up for I/O contention.
Having redo, rollback, temp, and system on mirrored devices is fine.
the system (C drive) and (E drive) will be partitioned on pair of mirrowed and they put all of the log files and system, rollback in there.
to me this configuration is not right but I like to prove it to them.