[dm-devel] dm-rdac not working?

[Tore Anderson]

* Chandra Seetharaman

> tur checker just sends a test unit ready to see if the path is good. 
> Whereas rdac sends a c9 page inquiry and determines the state of the 
> path.

   Okay.  I'm not really sure if I understand what practical difference
  there is between the two, though...  The TUR check seems to fail like
  it's supposed to if the path goes bad.

> That is true. But, I am wondering if what you have is based on the
> LSI Engenio based controller (and hence the controller does not
> understand the MODE_SELECT command).

   It's an Engenio 3994 that came with a sticker on it that says Sun
  StorageTek 6140.

> What mode do you have your storage device configured in ? rdac or AVT
> ?

   Host-type "Linux", which means RDAC (AVT is mostly unusable for
  clusters because of all the unwanted volume transfers it causes).  It's
  supposed to be used with LSI's RDAC 09.01.B2.xx driver, but that one
  doesn't work with recent kernels unfortunately.

> Where did you get mpath_prio_rdac from ?
> 
> In 0.4.7 you could use mpath_prio_tpc instead (it behaves exactly as 
> mpath_prio_rdac in 0.4.8).

   I got it from the 0.4.8 sources - mpath_prio_tpc complained a lot
  about AVT mode being disabled, which screwed up my multipath -ll output
  so I just got the new version instead.

> Can you apply the attached debug patch, repeat your test and send me
> the log.

   Sure, but I think you forgot to actually attach the patch... (Happens
  to me too all the time!)

Regards
-- 
Tore Anderson