MPS driver: force bus rescan after remove SAS cable

[Alexander Motin]

On 27.04.2011 16:39, Denny Schierz wrote:
> Am Mittwoch, den 27.04.2011, 05:57 -0700 schrieb Jeremy Chadwick:
>> camcontrol reset 0
>
> 0:22:0 is available, 0:46:0 not:
>
> root at iscsihead-m:~# camcontrol reset 0:22:0
> Reset of 0:22:0 was successful
>
> root at iscsihead-m:~# camcontrol reset 0:46:0
> camcontrol: cam_open_btl: no passthrough device found at 0:46:0

You should reset whole bus, not the specific LUN. Full reset doesn't 
need that passthrough device. IIRC it works via xpt0.

> We bought the LSI SAS6160 switch:
>
> http://www.lsi.com/storage_home/products_home/sas_switch/sas6100/index.html
>
> use the LSI 9200-8e hostbusadapter and LSI JBODs 630j. We had a lot of
> e-mail conversation with LSI and they mean, that we need the switch for
> a clear failover setup.
> Also a reason for the switch: increase storage with more jbods. Every
> jbod has his own cable to the (later) redundant switch. Otherwise we
> have to build a "bus" from JBOD to JBOD to JBOD to JBOD to host ... bad
> idea ;-)
>
> The question is, what does the driver while FreeBSD starts?

CAM exactly does full bus reset and after few seconds full rescan. What 
controller driver may do except it depends on it alone.

-- 
Alexander Motin