topic Re: 2 Network cards only in Operating System - HP-UX

2 Network cards only

Stefan Huber — Tue, 08 Feb 2011 15:57:05 GMT

Hi,

I have two servers with two network cards only.
I configure one interface (lan0) for heartbeat. The other interface (lan1) gets the servers physical ip.

What happens, if lan1 fails. Is service guard able to switch the package ip over to the heartbeat interface?

Cheers

Re: 2 Network cards only

Ismail Azad — Tue, 08 Feb 2011 17:43:39 GMT

Hi stefan,

As of my knowledge, an interface that has to act as a failover for another interface in terms of NIC or talking about the terminology "standby", one typical requirement being that the standy interface should not be configured with an IP address!!

This is one of the primary rules of classic serviceguard.

> Is service guard able to switch the package ip over to the heartbeat interface.

The package ip is supposed to be different from your stationary IP address in case of your scenario lan1. The "package" should be failing over to another node. You are talking about a standy lan interface if I am not mistaken . :)

Regards
Ismail Azad

Re: 2 Network cards only

Stefan Huber — Tue, 08 Feb 2011 18:03:12 GMT

Maybe I wasn't clear enough...
The servers have each two NIC's.
Lan0 is for heartbeat and is in the same vlan or network (e.g. 10.100.1.10)
Lan1 has a 10.100.1.20 ip address.
So, the question again:
Is serviceguard able to fail over from lan1:1 to lan0:1 if lan1 fails?

PS:
I now HP recommends that the heartbeat packages should go over an additional vlan/network.

Re: 2 Network cards only

Manix — Tue, 08 Feb 2011 19:19:31 GMT

I configure one interface (lan0) for heartbeat. >>The other interface (lan1) gets the servers physical ip.

>Lan0 is for heartbeat and is in the same vlan or network (e.g. 10.100.1.10)
>Lan1 has a 10.100.1.20 ip address.

Looks like both are in same network

You clearly said that the lan1 has physical IP,so it`s might be for heartbeat + data

lan0 has heart beat IP ,so it`s dedicated heartbeat ( no data )

PS ::check cluster.conf file for the same.

So you just have fulfilled the minimum cluster requirement.

If lan0 fails ,then both heartbeat + data may go through lan1.

But if lan1 fails there will be no data transfer only heartbeats.So there would be issues with data transactions.

Doesn`t looks like a very good setup ,good to have a standby heartbeat & data lan card.

Yes heartbeat & data are good to keep in different subnets.

Do post you cluster.conf file for further queries.

Hope this helps.

Manix

Re: 2 Network cards only

Ismail Azad — Tue, 08 Feb 2011 19:55:32 GMT

Hi,

Yes.... If you need a standby lancard you need one more NIC without an IP configured so as Manix said the failure of lan1 failsover where??

I know you know this but:-

One of the rules of serviceguard is to not put the same subnet for two interface cards on the same node of the cluster. This is not only for a serviceguard cluster but also a rule for troubleshooting network connectivity which states that if you do this, both your interface cards might not function "simultaneously" but might function separately. Jus curious but especially in a cluster environment why would u want this??

Regards
Ismail Azad

Re: 2 Network cards only

Stefan Huber — Tue, 08 Feb 2011 20:18:37 GMT

Thanks for all the answers.
I knew, that this configuration would fulfill the minimum requirements...

Re: 2 Network cards only

Stefan Huber — Tue, 08 Feb 2011 20:19:02 GMT

closed