Veritas DMP (Dynamic Multi Pathing) How to?

[Gene Laoyan]

Has anyone used this?
I have a LUN presented to our Integrity box and it comes up with two disk paths...

/dev/dsk/rdsk/c2t6d0
/dev/dsk/rdsk/c3t6d0

What do I need to do be able to use both paths as one in a failover scenario. From what I have read, using Veritas DMP you can create a disk group and access the disks via the group name. Unfortuneately I have little to no documentation on how to do this.

Any help would be appreciated.

Thanks

[Morcos]

Hi Gene,

1)Using LVM you can use one in a failover scenario. All what you have to do is:

pvcreate ... for the primary path
mkdir ..
mknode..

vgcreate /dev/vg0x /dev/dsk/rdsk/c2t6d0
vgextend /dev/vg0x /dev/dsk/rdsk/c3t6d0

2)Concerning veritas DMP:
-Is veritas installed on your machine with license to be able to use it?
-when veritas is installed the DMP is enabled by default, so from veritas you will see only one path.
To add a disk to veritas, the simplest way is to run the command: vxdiskadm
and you will have a menu you can chooose which option to use.

Hope this helps you.

Regards,
ziad

[Gene Laoyan]

Thanks for your sugestion. We're aware of pvlinks but it adds too much additional management on a serviguard failover. We want to only handle devicefiles. We have HP-UX MCOE 11.23 and I think it has Veritas DMP, I verified that it was installed. Do you have any examples on how to use DMP? I can not find any good examples for a newbie like myself.

Thanks

[pswma2]

Please check Volume Manager Admin Guide and man pages vxdmpadm.
You need Volume Manager to create a disk group.
You need Veritas DMP to control both paths to your LUN (load balancing, failover rtc.).