Two questions regarding the CERC SATA1.5/6ch RAID controller

David Kinnvall david.kinnvall at alertir.com
Mon May 10 09:33:00 CDT 2004


Following up my previous message, answering the first question
and asking/amending the second one again. See below, please.

David Kinnvall (me) wrote:

[snip]

> Now, my questions:
> - Can the CERC SATA1.5/6ch available for the 700 handle RAID10 ?

After putting additional pressure on Dell's Swedish tech support,
the answer to the above question became "Yes". Good. Additional
drive has been ordered.

As for the second:

> - Can I migrate the already created RAID5 array to a RAID10 array
>   "online", without starting from scratch? If possible, what are
>   the steps in either the BIOS screen(s) or (preferably) in afacli?

Tech support could not answer this, with neither yes nor no.

The docs for the CERC SATA1.5/6ch, available (starting) at
http://docs.us.dell.com/docs/storage/cerc/, say, and I quote:

"Online RAID Level Migration—Lets you change RAID levels without
rebuilding your array from scratch."

followed a bit later by:

"Table 1-1. Array Migration Possibilities

Current Array Type  New Array Type
  RAID 0              RAID 5 or 10
  RAID 1              RAID 0 or 5 or 10
  RAID 5              RAID 0 or 10
  RAID 10             RAID 0 or 5"

I have RAID5 now, and want to move to RAID10 using the fourth
disk when it arrives. According to the above table that should
be possible, as far as I can see. So:

- Does anybody know whether it actually *is* possible?

- Does anybody know the precise command sequence in either
   the BIOS or (preferably) in afacli to do the migration,
   ideally also incorporating the steps needed to get the
   new fourth drive online as part of the process?

Any help greatly appreciated!

Best regards,

David




More information about the Linux-PowerEdge mailing list