How to update Cluster device special files for new devices

[David Dilly]

Hello,

My cluster is up and running (11.20 and 11.31).
I used cDSFs for my volume groups.

But today, i presented a new device on the 2 cluster nodes and the cDSFs are not created automatically.

I's there a command to scan the device on the 2 nodes to create the cDSFs files ?

thanks.

[g3jza]

Hi,
you need to run 'ioscan -fn' . Then on 11.20 you also need to run 'insf -e -C disk' command, so the DSF's get created. On 11.31 , you don't have to run the 'insf' command, the DSF will be created for you automatically.

[David Dilly]

Hello,

Thanks, but it's not /dev/disk or /etc/dsk.

It's /dev/cdisk (cluster device special files).

It's not the same procedure for this type of special files .....

[David Dilly]

The device special files looks like :

disk 41 64000/0xfa00/0xe esdisk CLAIMED DEVICE HP OPEN-V
/dev/cdisk/disk9 /dev/disk/disk41 /dev/rcdisk/disk9 /dev/rdisk/disk41

disk 42 64000/0xfa00/0xf esdisk CLAIMED DEVICE HP OPEN-V
/dev/cdisk/disk10 /dev/disk/disk42 /dev/rcdisk/disk10 /dev/rdisk/disk42

disk 43 64000/0xfa00/0x10 esdisk CLAIMED DEVICE HITACHI OPEN-V
/dev/disk/disk43 /dev/rdisk/disk43

[g3jza]

Oooh I see, don't have any experience with this, I'm sorry...

[g3jza]

So the ioscan & insf didn't help, right?

[David Dilly]

No

[g3jza]

I've found some article talking abou cDSFs:

http://www.hpuxtips.es/?q=node/263

May be of help

[g3jza]

As I'm quickly reading throught it, it also contaings the procedure for converting regular DSF to cDSF, so it should answer your question :) .

[David Dilly]

I red it, in this documentation, we can see that :

HP-UX automatically creates new cDSFs when you add shared storage

Strange .......not on my systems ....

[sangilak]

Hi,


Although I do not have any experience with cDSF, I believe you need look into the 'cmsetdsfgroup' command.

A copy/paste from the 'io_cdsf_config' manpage:

"Cluster device special files provide a consistent set of device special files across a set of cluster nodes. The cluster device special files of a LUN will be the same on any node in a specified set of nodes that share the LUN. The set of cluster nodes across which cluster device special files need to be created can be specified using the command cmsetdsfgroup. (see cmsetdsfgroup(1M)).

The cluster device special file daemon iocdsfd is responsible for creating the cluster device special files across a cluster. The user must execute:
# cmsetdsfgroup [-n node_name] [-n node_name]...
to initiate cluster device special file creation. Cluster device special file daemon iocdsfd creates the block and character device special files in the /dev/cdisk and /dev/rcdisk directories, respectively."

Source:
http://h20000.www2.hp.com/bc/docs/support/SupportManual/c02258077/c02258077.pdf


Hope that helps,

sangilak

[KathyL1]

I recently implemented cDSFs in our test environment but after doing so Ignite-UX started issuing warnings in relation to them.

I logged a support call with HP in relation to this issue and received the following response:

"Ignite-UX does not support Cluster Device Special Files (cDSFs) in an Serviceguard environment. Recovery support for such a configuration has not been tested and is not supported. If you require support for recovery archives in a Serviceguard environment do not implement cDSFs."

The Serviceguard lab are going to add Ignite-UX into their release notes as not supporting cDSFs.

At this point in time you have to choose between implementing cDSFs and being able to recover a system using Ignite-UX.