Subscribe

HPUX host utilities changing active/active PVlinks to active/passive

Good morning,

We have replaced EMC in a large government organisation and slowly building up an environment that the customer is happy with.

They have experienced less than expected performance (when compared with the old clariion) and I am trying to understand why (it could be perception).

A “sanlun lun show –p” shows me multi-pathing as A/A and failover provider as HP PV Links which I believed is only A/P capable (or was). 

rdlisla2# sanlun lun show -p

MDSVRFAS01A:/vol/RDLISLA2UTILS/QTRDLISLA2UTILSLUN11/RDLISLA2UTILSLUN11.LUN (LUN 111)
Agile Filename: /dev/rdisk/disk38       VG: /dev/vgutils
   200g (214748364800)   lun state: GOOD
Filer_CF_State: Cluster Enabled  Filer Partner: MDSVRFAS01B
Multipath_Policy: A/A
Multipath_Provider: HP PV Links
-------- --------- -------------------- ------ ------- ------- -------------
host     filer                 /dev/dsk        primary partner PVlinks
path     path                  filename host   filer   filer   path failover
state    type          or Hardware Path HBA    port    port    priority
-------- --------- -------------------- ------ ------- ------- -------------
up       primary      /dev/dsk/c19t13d7 fcd0   0d              0
up       primary      /dev/dsk/c16t13d7 fcd1   0h              1
up       secondary    /dev/dsk/c20t13d7 fcd0           0d      2
up       secondary    /dev/dsk/c17t13d7 fcd1           0h      3

A vgdisplay shows,

rdlisla2# vgdisplay -v /dev/vgutils

--- Volume groups ---

VG Name                     /dev/vgutils

VG Write Access             read/write

VG Status                   available

Max LV                      255

Cur LV                      3

Open LV                     3

Max PV                      255

Cur PV                      2

Act PV                      2

Max PE per PV               8000

VGDA                        4

PE Size (Mbytes)            32

Total PE                    12798

Alloc PE                    10974

Free PE                     1824

Total PVG                   0

Total Spare PVs             0

Total Spare PVs in use      0

VG Version                  1.0

VG Max Size                 63750g

VG Max Extents              2040000

   --- Logical volumes ---

   LV Name                     /dev/vgutils/lvol1

   LV Status                   available/syncd

   LV Size (Mbytes)            32000

   Current LE                  1000

   Allocated PE                1000

   Used PV                     1

   LV Name                     /dev/vgutils/lvol2

   LV Status                   available/syncd

   LV Size (Mbytes)            19168

   Current LE                  599

   Allocated PE                599

   Used PV                     1

   LV Name                     /dev/vgutils/lvol3

   LV Status                   available/syncd

   LV Size (Mbytes)            300000

   Current LE                  9375

   Allocated PE                9375

   Used PV                     2

   --- Physical volumes ---

   PV Name                     /dev/dsk/c19t13d6

   PV Name                     /dev/dsk/c16t13d6        Alternate Link

   PV Name                     /dev/dsk/c20t13d6        Alternate Link

   PV Name                     /dev/dsk/c17t13d6        Alternate Link

   PV Status                   available

   Total PE                    6399

   Free PE                     0

   Autoswitch                  On

   Proactive Polling           On

   PV Name                     /dev/dsk/c19t13d7

   PV Name                     /dev/dsk/c16t13d7        Alternate Link

   PV Name                     /dev/dsk/c20t13d7        Alternate Link

   PV Name                     /dev/dsk/c17t13d7        Alternate Link

   PV Status                   available

   Total PE                    6399

   Free PE                     1824

   Autoswitch                  On

   Proactive Polling           On

Could this be causing performance issues (as trying to use the alternate path and would have to time-out the requests that are sent down that path which – from memory – is around 60 seconds ).

If so, any idea how I can change it to be A/P

I look forward to any replies.

cheers

Mike

Re: HPUX host utilities changing active/active PVlinks to active/passive

Well to start  with A/A mode with PV links is not supported. If you wish to use PV Links that is has to be with A/P. Kindly run /opt/NetApp/santools/bin/enable_ontap_pvlinks

However A/A will give you better performance with ALUA/Native Mpio.

Re: HPUX host utilities changing active/active PVlinks to active/passive

The customer is telling me that enable_ontap_pvlinks has been run, yet it still shows A/A and PV links.

I am really looking at how I can change the PV links to A/P (and then take ALUA/MPIO multiplathing to them as an option).

I hope you can help.

cheers

Mike