iSCSI initiator and Dell PowerVault MD3000i

[Daniel Braniss]

> 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
> 
the numbers seem ok to me, concidering that the net is 1Gb.
can you configure the target virtual disk to have luns?
in any case the errors seem to be in the md3000i, can you see/check its
error log?

> 
> Do you have experiences with iSCSI multipath? I read about geom_fox and 
> gmultipath...
i have no experience with it, and personaly see no benefit in it (but then
others might disagree :-)

danny