HP-UX 11.31 unable to see changed LUN paths

[Rick vonR]

We are migrating from 11.11 PA to 11.31 IA.  One of the strange things we have found is that whenever a LUN path changes, 11.31 will not recognize the new LUN path nor the devices on it.  This happens when storage array paths or tape device paths change.  In 11.11 it would simply mark the old path as NO_HW and show the new paths.  But, in 11.31 it will show the NO_HW devices but will not show the new ones.  The error message in syslog is something like this:

Evpd inquiry page 83h/80h failed or the current page 83h/80h data do not match the prev
ious known page 83h/80h data on LUN id 0x0 probed beneath the target path (class = tgtpath, instance = 8) The lun path i
s (class = lunpath, instance 14).Run 'scsimgr replace_wwid' command to validate the change

So, I run that scsimgr command and I can get my new LUN paths.

I am having a particular problem with some tape devices on an ESL712e.  The ESL uses NS E2400FC routers (dual port FC).  Behind each port sits two LTO3 drives.  So, for each NS E2400FC WWN it finds, it should discover the two tape drives it is controlling.  When the router was first presented to the host, the host discovered the drives with no issue.  But, the LUN IDs of the tape devices have since changed and the 11.31 host refuses to find the new drives.  I know the host HBA can see the NS E2400FC router because I can see the WWNs in the output of "fcmsutil /dev/fclp2 get remote all". See below.

# fcmsutil /dev/fclp2 get remote all
<snip>
******************************************************************************
****                        Node Port Information                         ****
******************************************************************************


                        Target N_Port_id = 0x020600
                            Target state = ONLINE
                           Symbolic Name = HP      NS E2400FC      5963
                               Port Type = N_PORT
                           FCP-2 Support = YES
             Target Port World Wide Name = 0x100000e002433bbe
             Target Node World Wide Name = 0x100000e002033bbe

Common Service parameters (all values shown in hex):
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
         Common Features : c800                     RO_Bitmap: fe      
             Total Conseq: ff      

Class 3 Service parameters (all values shown in hex):
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
     Open Sequences/Exchg: 1                           Conseq: ff      
  Recipient Control Flags: 0                             Rxsz: 800     

 There are two tape drives behind that WWN and they will not show up.  All of my 11.11 hosts can see them just fine.  I ran a scsimgr command to try and replace the path but it did not work.

Questions:

1 - How can I get these drives to show up?

2 - Is there any way to have 11.31 automatically recognize changed LUN paths?

Thanks in advance for any help.

[EEESEC]

On 11iv3 persistent DSFs are used and should not (usually) be affected by changes to LUN paths. Check out the "HP-UX 11i v3 Persistent DSF Migration Guide" if you haven't already.  A google search should pull it up. 

Another possibility is the uEFI settings on your new IA servers.  I know for our BL860c I2 blades, unless we have the "EFIFCScanLevel" set to 1, it won't fully scan the fiber channel network for new luns.

[Rick vonR]

Thanks for the reply EEESEC.  We are running on a Superdome 2.  Would such a setting exist there?

[Michael Leu]

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@Rick vonR wrote:

1 - How can I get these drives to show up?

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On which LUNs are the drives presented?
I faintly recall on our ESL712e we had to always have one drive per port with LUN 0 or else nothing was seen behind that port.

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@Rick vonR wrote:
2 - Is there any way to have 11.31 automatically recognize changed LUN paths?

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There is no setting as far as I know. The WWIDs of all devices are kept in the kernel registry even, and even  if you remove a device the information stays in the registry.