iSCSI initiator and Dell PowerVault MD3000i

[Miroslav Lachman]

please Cc: me, I am not subscribed to freebsd-scsi

Sossi Andrej wrote:
 >> On 16. 12. 2009 15:57, Miroslav Lachman wrote:
 >> [...]
 >> I use MD300i with FreeBSD 7.0 and 7.1 with iscsi-2.2.2. It work fine.
 >> But be careful to configure MD3000i. MD3000i assign by default first
 >> disk to preferred controller 0, second disk to preferred controller 1,
 >> third disk to preferred controller 0, and so on. First, third, fifth...
 >> disks is usable from FreeBSD, but second, fourth,... disks result 
unusable.
 >> Work around: manually assign all disks to controller 0.
 >
 > When you say "unusable" do you mean you can't access it at all / it
 > errors even if it's the only path (drive) used? It would be normal if
 > you have for example two paths to each drive and can't mount the other
 > path if one path to the drive is mounted - this is not a usable
 > combination. You can use geom_multipath to get multipath failover.

I got errors even in unmounted state.
I tried iscsi-2.2.3 and got same errors. I tried second path first 
(device da0) and it produces same errors, then I run iscontrol for the 
first path (device da1) and everything is fine.

  ---- path throught second controller: ERROR ----
# diskinfo -t /dev/da0
/dev/da0
         512             # sectorsize
         2998998663168   # mediasize in bytes (2.7T)
         5857419264      # mediasize in sectors
         364607          # Cylinders according to firmware.
         255             # Heads according to firmware.
         63              # Sectors according to firmware.

Seek times:
         Full stroke:    diskinfo: read error or disk too small for 
test.: Invalid argument


  ---- path throught first controller: OK ----
# diskinfo -t /dev/da1
/dev/da1
         512             # sectorsize
         2998998663168   # mediasize in bytes (2.7T)
         5857419264      # mediasize in sectors
         364607          # Cylinders according to firmware.
         255             # Heads according to firmware.
         63              # Sectors according to firmware.

Seek times:
         Full stroke:      250 iter in   2.483517 sec =    9.934 msec
         Half stroke:      250 iter in   2.575778 sec =   10.303 msec
         Quarter stroke:   500 iter in   2.926170 sec =    5.852 msec
         Short forward:    400 iter in   0.916901 sec =    2.292 msec
         Short backward:   400 iter in   2.181790 sec =    5.454 msec
         Seq outer:       2048 iter in   0.520920 sec =    0.254 msec
         Seq inner:       2048 iter in   0.545300 sec =    0.266 msec
Transfer rates:
         outside:       102400 kbytes in   1.414997 sec =    72368 
kbytes/sec
         middle:        102400 kbytes in   1.454444 sec =    70405 
kbytes/sec
         inside:        102400 kbytes in   1.422527 sec =    71985 
kbytes/sec


Do you have experiences with iSCSI multipath? I read about geom_fox and 
gmultipath...

Miroslav Lachman