topic Re: Serviceguard in Operating System - HP-UX

Serviceguard

PVR — Wed, 07 May 2008 10:28:56 GMT

Hi !

I have one cluster of two nodes. There is a problem with one server and I halted NodeB. Now only NodeA is part of cluster. Assume that if the network team switches off all network devices (To which NodeA and NodeB connected).

Will NodeA TOC at this time ?

Thanks in advance !

Re: Serviceguard

Ramesh S — Wed, 07 May 2008 13:34:53 GMT

Hi

Since, you have halted the node B already, it seems that cluster is up & running with 1 node ( node A)

so there is no possibility of TOC'lng node A.

TOC happens on nodes which did not get cluster lock while clsuetr reformation.

Best Regards,
Ramesh

Re: Serviceguard

Yashwant — Wed, 07 May 2008 13:40:56 GMT

No...

If network team switched off all network devices then TOC will not take place...

Re: Serviceguard

PVR — Sat, 10 May 2008 08:17:11 GMT

Thanks for your replies.

I got a doubt here. When the network is down, service guard shall find the status of network on LAN1 is down and it will try to switch to LAN2. And it will not be able to find out a network there also. What will happen in this case ? Is it the way it works ?

Re: Serviceguard

PVR — Sat, 10 May 2008 08:20:07 GMT

Will it halt the package in this case ?

Re: Serviceguard

Sajjad Sahir — Sat, 10 May 2008 08:40:20 GMT

>>Will NodeA TOC at this time ?
answer is no
because if all network devices bring down u dont get transfer ok
why assume that if the network team switches off all network devices?
dear we can do a lot of things while cluster is running but in some cases we have to halt the cluster
for example
in case of lan card failure-u can do it in online and offline depending on u o/s and hardware running.here no need to halt the cluster.

please assign points

Thanks and regards

Sajjad Sahir

Re: Serviceguard

Mridul Shrivastava — Sat, 10 May 2008 10:35:00 GMT

This is not the way cluster works since that will be multiple point of failures since both the network cards are not able to connect to network.

MCSG is designed to provide redundancy for SPOF hence this will not work at all.

Re: Serviceguard

PVR — Sat, 10 May 2008 11:56:14 GMT

I agree that is a multiple point of failure.

Would like to know how MCSG reacts to this situation ?

Thanks

Re: Serviceguard

melvyn burnard — Sat, 10 May 2008 19:45:48 GMT

As one node has gracefully been removed from the cluster, you are now running a single node cluster.
If all the network links are cut or turned off, then the node will NOT TOC, but any package that is monitoring a subnet will see the subnet go down, and will halt.
I would recommend halting the cluster completely if you know this is going to happen

Re: Serviceguard

PVR — Sun, 11 May 2008 04:49:51 GMT

Thanks guys :)