HOWTO: Disk Mapping to client from dual VIOS using VSCSI and MPIO

Pre-Checks:

1) Update the adapter settings:

   # chdev -l fscsi0 -a fc_err_recov=fast_fail
   # chdev -l fscsi0 -a dyntrk=yes

2) Make sure that exported Lun exported from SAN should be available  in both the VIOS which is going to be mapped to client lpar through vscsi.

3) Set reserve_lock  to no for the disk which was added in both the vios from SAN.

Use the below commands to set it to no

   #chdev -l hdisk1 -a reserve_lock=no 
   #chdev -l hdisk1 -a reserve_lock=no  -P

4) Pre-check  whether disk was by mistakenly  used in any other client already

     #lqueryvg -Atp hdisk1

     root@vio1:/ #lqueryvg -Atp hdisk1
     0516-320 lqueryvg: Physical volume hdisk1 is not
      asigned   to  a volume group.
     0516-066 lqueryvg: Physical volume is not a volume group member.
     Check the physical volume name specified.
     root@vio1:/ #

Implementation:

5) Map the disk to the client from both the  vios check the diagram:

vioa:

#mkvdev -vdev hdisk1 -vadapter vhost1 -dev myvio1clivtd

viob:

#mkvdev -vdev hdisk2 -vadapter vhost1 -dev myvio2clivtd

Now in client:

6) Run config manager

#cfgmgr

root@cli1:/ #lspv
hdisk0          0004a256f06e0c6e      rootvg        active
hdisk1          0004a25613b2835f      datavg
hdisk2          0004a25613b287f1      datavg
hdisk3          0004a2561dc9d8bd      datavg
hdisk4          0004a2561dd57f15      datavg
hdisk5          0004a2561da57f16      None
root@cli1:/ #

7) Check the paths

root@orange-lpar:/ #lspath -l hdisk5
Enabled hdisk5 vscsi1
Enabled hdisk5 vscsi2

8) Check the path priorities

 # lspath -AE -l hdisk5 -p vscsi1
   priority 1 Priority True
 # lspath -AE -l hdisk5 -p vscsi2
   priority 1 Priority True

9) set path which was  from  viob to 2

 # chpath -l hdisk5 -a priority=1 -p vscsi1
 # chpath -l hdisk5 -a priority=2 -p vscsi2

Its done now ...

any questions ask@unixmantra.com