I needed to build a PowerHA cluster in the lab to test the upgrade process in isolation.  This meant I did not have access to any SAN storage that could be presented via NPIV to the cluster, so I used vSCSI devices from my test VIO Servers, as these had a couple of spare SAN disks that both VIO Servers could see.

At first I did not think that you could present vSCSI devices to multiple Clients at the same time, but I was wrong, you are allowed, it works, and both by PowerHA nodes now share the same vSCSI devices in a PowerHA cluster.

 

First, identify the common disks between the VIO Server pair - See my blog post for this.

http://www.capacityreports.net/AIX_Blog/admin.php?ctrl=items&blog=1&p=15

 

Then we can map the two hdiskpower devices to the first node.

# mkvdev -vdev hdiskpower9 -vadapter vhost2 -dev pocn070-dvg1

pocn070-dvg1 Available

# mkvdev -vdev hdiskpower10 -vadapter vhost2 -dev pocn070-dvg2

pocn070-dvg2 Available

 

Then we do the same for the second node, but I recieve an error telling me that the backing device is already in use.

# mkvdev -vdev hdiskpower9 -vadapter vhost3 -dev pocn071-dvg1

"hdiskpower9" is already being used as a backing device. Specify the -f flag
to force this device to be used anyway.

 

So I used the -f flag to mkvdev to force the mapping and this worked okay.

# mkvdev -f -vdev hdiskpower9 -vadapter vhost3 -dev pocn071-dvg1

pocn071-dvg1 Available

# mkvdev -f -vdev hdiskpower10 -vadapter vhost3 -dev pocn071-dvg2

pocn071-dvg2 Available

 

Running cfgmgr on the two clients shows both have two new hdisk devices.

# cfgmgr -l vscsi0

# cfgmgr -l vscsi1

 

Verify with lspv and lspath

# lspv
hdisk2    none    None
hdisk3    none    None
 

# lspath
Enabled hdisk2 vscsi0
Enabled hdisk3 vscsi0
Enabled hdisk2 vscsi1
Enabled hdisk3 vscsi1

 

Add the PVIDs on the nodes.

# chdev -l hdisk2 -a pv=yes

# chdev -l hdisk3 -a pv=yes

 

Verify the PVIDs with lspv.

# lspv

hdisk2    00123456789f23a9    None
hdisk3    00123456789f3c9c    None

 

Now continue with the PowerHA setup and configuration.