11iv3 server (Itanium) and using legacy device file names...

[Tom Haddad]

I have mapped some devices from my storage arrray (say 2). After masking to the host and running ioscan the host now sees them with a primary and alternate device file name for each.

When i extend my volumegroup with the first C/T/D..c11t0d1 ..no problem. When I extend the volumegroup with the aternate link ,, c12t0d1  for this same disk. It fails and  says

Verification of unique LVM disk id on each disk in the volume group /dev/vgxxx failed.

Following are the sets of disks having identical LVM disk id  /dev/dsk/c11t0d1  /dev/dskc12t0d1

So no alternate links in the volumegroup.

With agile paths mapped  to both primary and alternate legacy names (ioscan -m dsf) do I need to be concerned with adding the alternate links in the volumegoup?

[Earl_Crowder]

Tom,

When LVM barfs on adding an alternate path, something is out of whack.

What is the output of :

ioscan -m dsf /dev/dsk/c11t0d1

ioscan -m dsf /dev/disk/diskXXX  <-- from first ioscan

scsimgr get_info -D /dev/rdisk/diskXXX <-- from first ioscan

scsimgr lun_map -D /dev/rdisk/diskXXX  <--  from first ioscan

Earl

[Patrick Wallek · Accepted solution]

Your best bet is to use the persistent device file rather than the legacy.  That way you don't have to worry about what you do. 

Just add the /dev/disk/disk* device file and you are done.

To add it to an existing VG just do a 'vgextend /dev/vg?? /dev/disk/disk?

Then do a 'vgreduce /dev/vg?? /dev/dsk/c?t?d?'

Now you have the built-in multi-pathing.

[Tom Haddad]

Heres an update for  you and what I have learned

my ioscan -m dsf /dev/dsk/cxtxd0 shows  its  related  agile dsf. (ie /dev/disk/disk100)

When i run ioscan -m dsf /dev/disk/disk100 it shows only one legacy dsf (the primary ..no alternate)

IN other words ioscan -m dsf shows a unique agile dsf for every legacy dsf.

From a previous article I learned the issue may lie with my storage folks (EMC in this case) and that a bit may not be enabled to support 11iv3 thus a unique dsf (wwn) is generated for EVERY legacy dsf.

I dont know yet the impact if any on my systems when the bit is set.

At this time my volumegroup contains only  primary legacy dsfs only.

If there is anything else (from  HPUX side) i misunderstanding let me know.

I have an older 11iv3 server where the ioscan -m dsf output is fine.

Disk was allocated to it using a older EMC array.

[Tom Haddad]

so you are saying using the persitent names instead of legacy ..

1.  Current VGs have one legary (primary) disks right now .. (cant extend with the second alternate legcay name of course)

2   If I add the 2 persistet names for the same EMC device, I cant remove the one legacy.

As you know for each EMC disk i have 4 dsfs (show from ioscan -m dsf )

2  primary legacy and 2 alt persistent...

Do I just have the current VGs with primary legacy and one persistent name  AND next time i create  new VG used only the persistent names?