OFFSETs and LUN assignments

[Jay Richardson]

I've got an issue where our HP-UX servers were all configured with the same OFFSET "50" and therefore LUNS have been assigned from D50 - D59. If I assign a LUN say D61 to one of those servers, would they be able to see it, or would I need to install an additional FC card and configure it for a different offset?

Also, I am showing connections to the current FC cards that are offline but configured for offset "150". If I could get them online this could in essence allievate my problem. Yes?

[Uwe Zessin]

It depends on the adressing mode if HP-UX can see more than 8 LUNs on a target. Most systems use 'peripherical device LUN addressing', but HP-UX uses 'volume set addressing'. On recent ACS versions you can assign the HP_VSA mode to the CONNECTION (SET con OPERATING_SYSTEM=HP_VSA) and be able to address more than 8 LUNs through a CONNECTION.

If that doesn't work, we need more details to better help you. What ACS Version are you running? Do you have dual controllers and how are they configured? Transparent- or Multibus-failover? OFFSET 150 suggests a single controller or transparent-failover setup, but it could just be a stale entry. Does it stay OFFLINE after you do an I/O scan?

How are your HSG controllers connected to the switch(es)? It is important to know, because this can result in different CONNECTIONS. A change can leave stale connections which should be removed so that the internal connection table does not overflow.

Apart from that: yes, you can put an additional fibre channel adapter in your server and define different CONNECTION offsets so you can address another 8 LUNs.

Sorry, but there isn't enough info to give a fully satisfying answer - SAN management sometimes is a very tedious business.

[Jay Richardson]

What I'm working with is two HSG80 controllers configured for transparent failover. They are up to ACS V86S-12 currently. There are two switches with controller connections to each switch. Each controller is only active on opposite switches. The offline connections only pertain to my HP-UX servers. Windows and Netware connections are all online.

Thanks for you assistance.

Jay

[Uwe Zessin]

Too bad :-( I have checked the installation guide for HP-UX, I might have missed something, but it looks like ACS V8.6 does not have HP_VSA. It sounds like you are running in SCSI-2 mode and have the CCL disabled, right? Are you sure you can address 10 LUNs on a single controller-port?

If the LUN range (50..57) is taken up on one controller port you can add another range (150..157) on the other controller/port.

However you first need to find out why the fibre channel adapter has no commuication with the controller Port_2. Is there any zoning in effect?

[Jay Richardson]

Yep! SCSI-2 with CCL disabled.

Not all the LUNS go to the same controller they are distributed among four HP-UX servers.

I do have zones configured, one of which has only the HP-UX servers and both HSG80 controllers as members. Possibly something in the driver configuration on the FC card?

[Uwe Zessin]

I am not a HP-UX expert, but I think you can check their characteristics with a command like: '$ fcmsutil /dev/td0'

If you are allowed to post this output, the output from the 'switchshow' command on the FC-switches and a 'SHOW CONNECTIONS FULL' from the HSG80 as attachments (a simple cut&paste here seems to mess up the spaces) - I'm happy to take a look at it.

[Jay Richardson]

Here ya go. The file has both outputs

[Uwe Zessin]

Jay,
are you sure your zoning is correct? Take a look at the connections HP2K_11A/HP2K_22A or HP3L_11A/HP3L_22A: according to their WWNs it is the same adapter. Can you post a 'cfgshow' from one of the switches, too? (I'll see if I can look at it later this evening or tomorrow)

By the way: it looks to me that HP3L_11A/HP3L_22A has the wrong OPERATING_SYSTEM type set. Shouldn't this be HP instead of WINNT?

Also, it looks like 'SANAP' (whatever that is - Storage Management Appliance?) has no connection at all.

[Jay Richardson]

The zoning is pretty straight forward in this configuration. The only difference between the other HP connections and the 2K, 3L connections is only one FC adapter in the 2K and 3L.

Thanks for catching the 3L O/S type. Can that be changed to HP without issue?

The SANAP, yes SAN Management Appliance, is a connection not currectly in use, but the appliance does have an active connection SNAP2

[Uwe Zessin · Accepted solution]

Hm. I have never seen anyone put the WWNN (world wide node names - the HSG displays this as HOST_ID in the connection table) into the zones. I never had a problem using WWPNs only.

I think the safest way is to shut down HP3L, change the connection to OS=HP and then reboot the server.

While browsing over the connection table I beleive you have confused the assignment of HP3L_11A (which points to OTHER/Port_2) with HP3L_22A (which points to THIS/Port_1). All other connections seem to be the other way.
Also: shouldn't the HPL_11A connection have a UNIT_OFFSET of 150, too? The HP3L_22A has a value of 50 and HP2K_11A=50 / HP2K_22A=150.

Do this while you are changing the OS value:
SET HP3L_11A UNIT_OFFSET=150 ! I hope I got the syntax right

You can just rename them online:
RENAME HP3L_11A T_22A
RENAME HP3L_22A HP3L_11A
RENAME T_22A HP3L_22A

However, I have no real idea why your fibre channel adapters can't seem to connect to PORT_2 of the HSG. Let us try something out:

- create a unit D150 and present it via HP3L_22A after you have made the fixes:
ADD UNIT D150 container DISABLE_ACCESS_PATH=ALL
SET D150 ENABLE_ACCESS_PATH=HP3L_22A
- do an IOSCAN
- any change?