sgscan showing same tape drive & robot twice in solaris

[sysahamed]

Actually I had to reinstall one of my media server. I installed netbackup successfully & when i tried to configure tape drive, sgscan is showing same tape drive & robot twice in solaris. I tried to unconfigure it using cfgadm & it is giving me Configuration administration not supported.

[Will_Restore]

multipathing enabled?  that could do it.  we had a setup that way & it worked just fine.

[Marianne]

Please show us output of 
ls -l /dev/rmt/*cbn

This will confirm paths to devices.

Multipathing is fine as long as the device wizard is used for configuration.

[sysahamed]

Output of /dev/rmt/*cbn

/dev/rmt/0cbn -> ../../devices/pci@0/pci@0/pci@8/pci@0/pci@1/SUNW,qlc@0/fp@0,0/st@w500104f000b86275,0:cbn

 /dev/rmt/1cbn -> ../../devices/pci@0/pci@0/pci@8/pci@0/pci@1/SUNW,qlc@0/fp@0,0/st@w500104f000b8627b,0:cbn

/dev/rmt/2cbn -> ../../devices/pci@0/pci@0/pci@8/pci@0/pci@1/SUNW,qlc@0,1/fp@0,0/st@w500104f000b86278,0:cbn

/dev/rmt/3cbn -> ../../devices/pci@0/pci@0/pci@8/pci@0/pci@1/SUNW,qlc@0,1/fp@0,0/st@w500104f000b8627e,0:cbn

/dev/rmt/4cbn -> ../../devices/pci@0/pci@0/pci@8/pci@0/pci@9/SUNW,qlc@0,1/fp@0,0/st@w500104f000b86275,0:cbn

/dev/rmt/5cbn -> ../../devices/pci@0/pci@0/pci@8/pci@0/pci@9/SUNW,qlc@0,1/fp@0,0/st@w500104f000b8627b,0:cbn

My finding is that highlighted ones are the duplicated ones & this is getting detected thru another HBA. 

Multipathing

#mpathadm list mpath-support

mpath-support:  libmpscsi_vhci.so

#mpathadm list lu

I observed this error at the last after listing logical units.

mpathadm:  Error: Unable to get configuration information.

mpathadm: Unable to complete operation

[Marianne]

Solaris multipathing is meant for disk, not tape. 

Is your media server Solaris SPARC or x86?

Extract from Device Config Guide

Configuring Solaris 10 x86 for multiple drive paths

To use multiple paths to the same tape drive, NetBackup requires that Solaris

Multiplexed I/O (MPxIO) be disabled. MPxIO is enabled by default on Solaris 10

x86 systems.

[sysahamed]

Media server is Solaris SPARC & another thing i noticed is four HBAs online in this server compared to two online in other media servers. 

[sysahamed]

Marianne can you assist me further on this?

[mph999]

Fix your zoning - I suspect you have the drives zoned in twice.

Martin

[sysahamed]

Can i ignore duplicate one & configure it?

[mph999]

It'll just configure with mutiple paths as long as you use the wizard.

BUT

Clearly this is not how the system was designed, as you have rasied the concern.  So you should fix the problem, not ignore it.

It is not difficult to check zoning and unzone drives.

I think you need to sit down and lok at the design documets to see how the drives are meant to be attached, and see what the design document for the zoning says.

Martin

[Marianne]

Yes, just use the wizard to config.

I was involved in big customer installation about a year ago with multiple Solaris Sparc media servers.
They had dual paths to the tape drives - /dev/rmt entries as well as sgcan showed 2 paths.

All worked fine using the wizard to config.

With more and more media servers being added to the 'mix' and due to the amount of devices and paths, the GUI wizard started to timeout.
We then opted for command line config where timeout can be specified:

vmoprcmd -h <media-server-name> -timeout 3600 -autoconfig  -a

[sysahamed]

In the wizard i just removed the duplicate path for the tape drives & went ahead but the wizard finally get hanged at restarting device manager daemon.

[Marianne]

If you don't want multipathing on your tape drives, fix the zoning.

[sysahamed]

How to proceed as the wizard has got hanged? Shall i delete the drives & reconfigure...

[mph999]

You could try that.

Is the OS still seeing each drive twice ?

Martin

[mph999]

You removed the paths in the wizard, as clearly, you don't want multiplathing.

In my advice before, I said to remove the zoning if you don't want multiplathing.

What you will end up with, potentially, is drives configured on one path, buth that have an extra' unused path.

Can you images how confusing this will be to the next TSE who looks at this system.

This is the perfect example of how not to do things - it leads to systems in such a mess that future troubleshooting gets very complex, and very very time consuming.

I asked a previous question:

What does you design document/ system documentation show for this system ?

You never gave an answer to this.  You need to know what should be there.

Martin

[Marianne]

In support of Martin's question:

What does you design document/ system documentation show for this system ?

Does each device actually have 2 fiber ports? Each zoned to different hba?
Or one drive connection zoned to 2 hba's?

[sysahamed]

One drive connection zoned to 2 hbas...

[Marianne]

Nope. Fix zoning to one hba only.

NBU Device Multipathing is meant for connectivity to dual-port devices.

I can unfortunately not find any documentation with requirements/instructions - just know this from experience.

I have asked a couple of Symantec gurus (including Martin) to help find such documentation.

[sysahamed]

Thanks Marianne...I need some couple of days to fix this as i am not a SAN admin.