LV strict option

[John Guster]

# lvdisplay -v /dev/vg00/lvol12
--- Logical volumes ---
LV Name /dev/vg00/lvol12
VG Name /dev/vg00
LV Permission read/write
LV Status available/syncd
Mirror copies 1
Consistency Recovery MWC
Schedule parallel
LV Size (Mbytes) 4096
Current LE 512
Allocated PE 1024
Stripes 0
Stripe Size (Kbytes) 0
Bad block on
Allocation strict
IO Timeout (Seconds) default

--- Distribution of logical volume ---
PV Name LE on PV PE on PV
/dev/dsk/c1t0d0 512 1024

--- Logical extents ---
LE PV1 PE1 Status 1 PV2 PE2 Status 2
00000 /dev/dsk/c1t0d0 02300 current /dev/dsk/c1t0d0 03387 current
00001 /dev/dsk/c1t0d0 02301 current /dev/dsk/c1t0d0 03388 current
00002 /dev/dsk/c1t0d0 02302 current /dev/dsk/c1t0d0 03389 current
00003 /dev/dsk/c1t0d0 02303 current /dev/dsk/c1t0d0 03390 current
00004 /dev/dsk/c1t0d0 02304 current /dev/dsk/c1t0d0 03391 current

Isn't it strange that lv has strict policy, but it is mirrored to the same physical volume?
Any suggestion?

[Pete Randall]

It's not that strange - unusual that someone would do it, but certainly not impossible. Apparently the LV was defined without strict allocation, mirrored, then changed to have strict allocation (see "man lvchange"). I can't even begin to imagine the explanation for such a scenario, though.


Pete

[Pete Randall]

Hmmmm. I was just reviewing the lvchange man page and it says the following changes are not allowed when a LV is mirrored:

+ From nonstrict to strict
+ From nonstrict to PVG-strict
+ From strict to PVG-strict

So now I'm wondering how someone accomplished this configuration at all!!


Pete

[Sandman!]

Your lvol resides on a single PV so the strict allocation policy does not make sense in this case.

[John Guster]

no idea how it happened. Thanks for checking.