topic Re: serviceguard in Operating System - HP-UX

serviceguard

p7 — Tue, 10 May 2005 12:01:48 GMT

hi all,

we have an app that is keyed to hostnames, in a 2 node cluster if the primary node (hostA) fails over to its secondary node (hostB), does
the secondary node get the primary nodes hostname? in other words does the hostname also failover?

thx in advance

Re: serviceguard

Denver Osborn — Tue, 10 May 2005 12:05:15 GMT

You'd want to tie your app to the floating ip address so that when the package fails over, your users can still get to it. :)

to answer your question, no the hostname will not failover in the way you described.

hope this helps,
-denver

Re: serviceguard

Steven E. Protter — Tue, 10 May 2005 12:17:35 GMT

hostname is unique to each host. The SG configuration refers to the hostname of the machine.

You can configure a floating IP address and a unqiue hostname for that ip address can be available on your network via /etc/hosts or DNS server.

Then no matter which node the application is running on the users just connect and don't really know the difference.

SEP

Re: serviceguard

A. Clay Stephenson — Tue, 10 May 2005 12:18:01 GMT

No. Your clients need to connect to the package hostname rather than the actual hostname. This is fundamental to the operation of MC/SG. If you had 3 packages, each would get a hostname/IP address and your clients wouldn't care what the actual server was.

Re: serviceguard

Rita C Workman — Tue, 10 May 2005 12:40:33 GMT

hostname of a server...belongs to the server, it doesn't failover.

We always point everything to resolve to the package name ! That way, it doesn't matter what server it is running on.
Even the Oracle desktop tnsnames uses the pkg name ... no IP...no hostname...just the package names. Works for local failover and even for when we failover to a different site !

Rgrds,
Rita

Re: serviceguard

Kent Ostby — Tue, 10 May 2005 13:33:12 GMT

You CAN assign a hostname to the floating IP address and then your users could use that no matter which system the package was running on .

Best regards,

Kent M. Ostby

Re: serviceguard

Stephen Doud — Wed, 11 May 2005 08:23:47 GMT

Once in a while a customer them will try to outsmart the application- they change the hostname of the server after the package starts on it. However, changing the hostname after starting the package will break serviceguard commands.

Re: serviceguard

Rita C Workman — Wed, 11 May 2005 08:38:42 GMT

A way to get your application to run on either would be to use a variable instead of the hostname. Or....what about this:

We had a problem with the new Oracle GL. Seems it integrates the hostname when it loads the software....but we found they had an option to enter a "logical" name when you load up the software. We entered the package name...and voila, it will even failover now using the package name.

Just some food for thought,
Rita