topic Re: Standby Lan config question in Operating System - Linux

Standby Lan config question

C Lamb — Thu, 11 Dec 2008 16:48:58 GMT

I am building a 2 node MCSG cluster on Red Hat 5 and have a question on the lan config. It used to be you specified the primary interface and a standby, but the 11.18 instructions dont cover that option, rather they "recommend" you use channel bonding. We have had issues with linux and channel bonding so I would prefer setting up the primary/standby config. Below is the cut from the config file complaining there are no standby interfaces, even though they are clearly on the same subnet. The warining note clearly suggest a primary/stanby option is available.

NODE_NAME billdb01a
NETWORK_INTERFACE eth2
STATIONARY_IP 10.10.191.53
NETWORK_INTERFACE eth3
HEARTBEAT_IP 10.1.0.1
NETWORK_INTERFACE eth0
STATIONARY_IP 10.10.191.50
NETWORK_INTERFACE eth1
HEARTBEAT_IP 10.0.0.1
# CLUSTER_LOCK_LUN

# Warning: There are no standby network interfaces for eth2,eth0.
# Warning: There are no standby network interfaces for eth3.
# Warning: There are no standby network interfaces for eth1.

SO can anyone point me to documentation on configuring primary/standby lan for MCSG on Linux?

P.S. please no answers questioning not using channel bonding, we dont want to do that.

Re: Standby Lan config question

Steven E. Protter — Thu, 11 Dec 2008 19:30:41 GMT

Shalom,

Check the release notes, but you should still be able to configure a stand by LAN. I do not think that feature was made obsoleted.

The configuration is not going to be different than other versions of SG.

If I'm wrong and the feature is obsolete (Its still there in HP-UX SG) then you may have to use a previous version of SG to avoid channel bonding(Which I use often with no ill effects).

SEP

Re: Standby Lan config question

C Lamb — Thu, 11 Dec 2008 19:33:29 GMT

Started with the release notes A11.18 May 2008. I couldnt find anything except channel bonding.

Re: Standby Lan config question

C Lamb — Thu, 11 Dec 2008 19:35:44 GMT

And yes I agree, I have been building MCSG clusters on HP-UX for over 10 years without issue. this is only my second Linux based MCSG cluster and that one didnt properly identify the standy either.

Re: Standby Lan config question

C Lamb — Thu, 11 Dec 2008 19:52:36 GMT

In an interesting note, but not one that resolves the issue, I reread the section on redundant network components in the install guide ( B9903-90060 Mar 2008 ) and noticed a nore to use the -w full option on cmquerycl to force discovery across routers and got the following;

NODE_NAME billdb01a
NETWORK_INTERFACE eth2
HEARTBEAT_IP 10.10.191.53
NETWORK_INTERFACE eth3
HEARTBEAT_IP 10.1.0.1
NETWORK_INTERFACE eth0
HEARTBEAT_IP 10.10.191.50
NETWORK_INTERFACE eth1
STATIONARY_IP 10.0.0.1
# CLUSTER_LOCK_LUN

# Primary Network Interfaces on Bridged Net 1: eth2,eth0.
# Warning: There are no standby network interfaces on bridged net 1.
# Primary Network Interfaces on Bridged Net 2: eth3.
# Warning: There are no standby network interfaces on bridged net 2.
# Primary Network Interfaces on Bridged Net 3: eth1.
# Warning: There are no standby network interfaces on bridged net 3.

note it even recognizes eth0 and eth2 on the same network but wont Primary/Standby with them.

Re: Standby Lan config question

John Bigg — Fri, 12 Dec 2008 08:47:08 GMT

Serviceguard Linux has never had a concept of a standby lan and you MUST use channel bonding to get redundancy. On Serviceguard HP-UX there is a whole network sensor subsystem which monitors lans at a link level and allows failover to a standby. This simply does not exist on Linux and we monitor the lan status using kernel ioctls.

This does not include the functionality required for standby failover so bonding needs to be used to achieve this.

Any references to standby lans you see in older SG/LX manuals are incorrect and are a hangover from the original HP-UX manual the Linux manuals were derived from. No SG/LX release has supported or had standby lan functionality.

So, sorry, I know you did not want an answer directing you back to channel bonding, I am not questioning this decision but if you want redundancy on a single lan this is your only option.

Re: Standby Lan config question

John Bigg — Fri, 12 Dec 2008 08:52:09 GMT

P.S. The warning does not imply standby functionality is available. It's just shared code between the HP-UX version and the Linux version. You could say that this should not be printed out on Linux, but the fact is that it is and because we do not setup any standby lan structures which still exist within the code you get a message which indicates there is no standby.

The truth is that there are no standby network interfaces because the functionality does not exist.

Re: Standby Lan config question

C Lamb — Fri, 12 Dec 2008 14:57:12 GMT

Thanks for the info. I had suspected as much, how does one submit to HP that a statement on this in the manual would be helpful! ;)

Re: Standby Lan config question

John Bigg — Sat, 13 Dec 2008 11:01:19 GMT

you just did ;-)