This is a most interesting thread. I'm a little be-fuddled, though.
How will ZFS know to select the RAID-Z2 stripes from each FLX380,
because if it stripes the (5+2) from the LUNS within one FLX380, this
will not help if one frame goes irreplaceably out of service.
Let's say the devices are named thus (and I'm making this up):
/devices/../../SUNW,[EMAIL PROTECTED]/[EMAIL PROTECTED],0/WWN:sliceno
[EMAIL PROTECTED] denotes the FLX380 frame, [0-6]
[EMAIL PROTECTED],n denotes the virtual disk,LUN, [0-19],[0-3]
How do I know that my stripes are rotated among [EMAIL PROTECTED], [EMAIL PROTECTED], ... [EMAIL PROTECTED]
When I make pools I don't give the raw device name, and ZFS may not
know it has selected its (5+2) stripes from one frame. This placement
is for redundancy, but then will I be wasting the other 79 spindles in
each frame? It's not just 7 giant disk.
If I needed to see this for myself, or show it to a customer, what test
may I set up to observe RAID-Z2 in action, so that I/O are observed to
be spread among the 7 frames? I'm not yet comfortable with giving ZFS
entire control over my disks without verification.
_______________________________________________
zfs-discuss mailing list
zfs-discuss@opensolaris.org
http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
