why not use the raid group plex mirroring already provided in OnTap ? from the 6.4.1 "vol" man page:
vol create volname [ -r raidsize ] [ -l language_code ] [ -f ] [ -m ] [ -w ] [ -n ] { ndisks[@size] | -d disk1 [ disk2 ... ] [ -d disk1 [ disk2 ... ] ] }
Creates a new volume with the name volname. The volume name can contain letters, numbers, and the underscore character(_), but the first character must be a letter or underscore. You can create up to 200 volumes on each filer.
...
The -m option can be used to specify that the new volume be mirrored (have two plexes) upon creation. If this option is given, then the indicated disks will be split across the two plexes. By default, the new volume will not be mirrored.
...
means you need more spindles, but that's what mirrors are all about.
-skottie
Bruce Arden wrote:
Our company (in its wisdom) has decided that all "critcal" data must be on mirrored filesystems, not on raid.
On filers, if you set the raidsize to 2, you effectively get a mirrored volume.
Does anyone do this? Does it cause a performance problem? Is there a limit on the number of raid groups in a volume?
- Bruce