Qlogin, Powerpath and too many paths to the same disk

SpLaSh212 · 03-01-2009, 09:52 AM

Hey,
My server is Red Hat Enterprise Linux Server release 5.2 (Tikanga),
Kernel Version is 2.6.18-92.el5
Powerpath version is EMCpower.LINUX-5.1.2.00.00-021

qla2xxx module is loaded

The Qlogic is dual port hba, with 2 zones total (one for each port),
Its connected to Symmetrix DMX 3000 machine with 1 disk masked to the host.
but when I run syminq is get

Code:

        Device                 Product                   Device
--------------------- --------------------------- ---------------------
Name           Type   Vendor    ID           Rev  Ser Num      Cap (KB)
--------------------- --------------------------- ---------------------
/dev/sda              EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdb              EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdc              EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdd              EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sde              EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdf              EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdg              EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdh              EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdi              EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdj              EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdk              EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdl              EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdm              EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdn              EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdo              EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdp              EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdq              EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdr              EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sds              EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdt              EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdu              EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdv              EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdw              EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdx              EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdy              EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdz              EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdaa             EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdab             EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdac             EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdad             EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdae             EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdaf             EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdag             EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdah             EMC       SYMMETRIX    5671 2200C3C000      46080
/dev/sdai             EMC       SYMMETRIX    5671 220110A008   31449600
/dev/sdaj             EMC       SYMMETRIX    5671 220110A008   31449600
/dev/emcpowera        EMC       SYMMETRIX    5671 220110A008   31449600

and powerpath showing

Code:

Pseudo name=emcpowera
Symmetrix ID=000287890722
Logical device ID=110A
state=alive; policy=SymmOpt; priority=0; queued-IOs=0
==============================================================================
---------------- Host ---------------   - Stor -   -- I/O Path -  -- Stats ---
###  HW Path                I/O Paths    Interf.   Mode    State  Q-IOs Errors
==============================================================================
   0 qla2xxx                   sdaa      FA  3aB   active  alive      0      0
   0 qla2xxx                   sdab      FA  3aB   active  alive      0      0
   0 qla2xxx                   sdae      FA  3aB   active  alive      0      0
   0 qla2xxx                   sdaf      FA  3aB   active  alive      0      0
   0 qla2xxx                   sdai      FA  3aB   active  alive      0      0
   0 qla2xxx                   sdaj      FA  3aB   active  alive      0      0
   0 qla2xxx                   sdb       FA  3aB   active  alive      0      0
   1 qla2xxx                   sdd       FA  7aA   active  alive      0      0
   1 qla2xxx                   sdg       FA  7aA   active  alive      0      0
   1 qla2xxx                   sdh       FA  7aA   active  alive      0      0
   1 qla2xxx                   sdk       FA  7aA   active  alive      0      0
   1 qla2xxx                   sdl       FA  7aA   active  alive      0      0
   1 qla2xxx                   sdo       FA  7aA   active  alive      0      0
   1 qla2xxx                   sdp       FA  7aA   active  alive      0      0
   1 qla2xxx                   sds       FA  7aA   active  alive      0      0
   1 qla2xxx                   sdt       FA  7aA   active  alive      0      0
   0 qla2xxx                   sdw       FA  3aB   active  alive      0      0
   0 qla2xxx                   sdx       FA  3aB   active  alive      0      0

As you can see, the OS sees too many paths, any1 got an idea how I can fix it ?

thnx in advance !

ringoSA · 03-05-2009, 07:55 AM

We are having exactly the same issue - did you ever manage to resolve this problem?

SpLaSh212 · 03-05-2009, 10:08 AM

We are very close, with your help we can isolate even more the problem.
I'm kinda sure of what is the problem, and this is the same thing that EMC thinks ...

Can u post the output of the following command:

Code:

symcfg -sid XXX -dir XX -p X -v list

where XXX is your machine, and XX is the FA and the X is the port

thnx !

ringoSA · 03-06-2009, 02:49 AM

Success!

Basically the SPC-2 bit needs to be set to correct this pathing issue - this can be done on a per host basis using wwn:

Code:

symmask -sid 679 set hba_flags on SPC2 -enable -wwn XX -dir YY -p ZZ

A quick reboot later and powerpath is now showing the right number of paths:

Code:

symmaskdb -sid AA list database -v -dir YY -p ZZ

   Originator Port wwn  : XX
   Type                 : Fibre
   User-generated Name  : XX
   Visibility           : No
   FCID Lockdown        : No
   Lun Offset           : No
   Heterogeneous Host   : No
   Port Flag Overrides  : Yes
     Enabled            : SPC2_Protocol_Version(SPC2)
     Disabled           : N/A
   Dynamic Addressing   : N/A
   Authentication State : N/A

The important bit is the SPC2 Port Flag override (we did it on overrides as these ports also support Solaris hosts).

Credit to EMC for this fix.

SpLaSh212 · 03-07-2009, 12:44 PM

The SPC2 bit was also the first though when we called EMC support team,
but, we have 2 machines, DMX3 and DMX3000 and I created zoned from both machines, and masked 1 disk from each of the machines, everything was fine on the DMX3, but the DMX3000 showed alot of paths.

When we checked the flags on the two FA's, they both were SPC2 disabled, and the only difference was the SCSI3 flag ! :/

If u say that the SPC2 flag fixed the issue, I think i'm going to try this, bc the SCSI3 flag cannot be set per host basis ...