[gpfsug-discuss] Dell Multipath

[Edward Wahl]

Sounds like too wide of a blacklist.   Have you specifically added the MD
devices to the blacklist_exceptions?   What does the overall blacklist and
blacklist_exceptions look like?   A quick 'lsscsi' should give you the
vendor/product to stick into the blacklist_exception.  

Wildcards work with quotes there, as well if you have multiple similar but not
exact enclosures.

eg:  "IBM      1818      FAStT"  can become:
        device {
                vendor "IBM"
                product "1818*"
        }
or Dell MD*, etc.

If you have issues with things working in the interactive mode or debug
mode (which usually turns out to be a timing problem) run a "multipath -v3" and
check the output.  It will normally tell you exactly why each disk device is
being skipped.  Things like "device node name blacklisted" or whitelisted.

Ed Wahl
OSC


On Mon, 25 Apr 2016 20:27:13 +0000
Jan Finnerman Load <jan.finnerman at load.se> wrote:

> Hi,
> 
> I realize this might not be strictly GPFS related but I’m getting a little
> desperate here… I’m doing an implementation of GPFS/Spectrum Scale 4.2 at a
> customer and struggle on a question of disk multipathing for the intended NSD
> disks with their direct attached SAS disk systems. If I do a multipath –ll,
> after a few seconds I just get the prompt back. I expected to see the usual
> big amount of path info, but nothing there.
> 
> If I do a multipathd –k and then a show config, I see all the Dell disk luns
> with reasonably right parameters. I can see them as /dev/sdf, /dev/sdg, etc.
> devices. I can also add them in PowerKVM:s Kimchi web interface and even
> deploy a GPFS installation on it. The big question is, though, how do I get
> multipathing to work ? Do I need any special driver or setting in the
> multipath.conf file ? I found some of that but more generic e.g. for RedHat
> 6, but now we are in PowerKVM country.
> 
> The platform consists of:
> 4x IBM S812L servers
> SAS controller
>   PowerKVM 3.1
> Red Hat 7.1
> 2x Dell MD3460 SAS disk systems
> No switches
> 
> Jan
> ///Jan
> 
> [cid:E11C3C62-0896-4FE2-9DCF-FFA5CF812B75]
> Jan Finnerman
> Senior Technical consultant
> 
> [CertTiv_sm]
> 
> [cid:621A25E3-E641-4D21-B2C3-0C93AB8B73B6]
> Kista Science Tower
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> Mobil: +46 (0)70 631 66 26
> Kontor: +46 (0)8 633 66 00/26
> jan.finnerman at load.se<mailto:jan.finnerman at load.se>



-- 

Ed Wahl
Ohio Supercomputer Center
614-292-9302