[Linux-cluster] multicast howto

[Greg Forte]

well, for starters, you've got three nodes but are using the two_node 
mode ... I'm pretty sure that won't work.

Also, I believe you need one multicast address that all the nodes 
communicate on - the multi-homed example given on that wiki page is 
intended for failover situations, not for "split-brain" networking ... I 
think.  And the addresses given there are just examples, you're going to 
need to explicitly configure your router(s) to send packets addressed to 
some multicast address that you assign for the cluster to the ports that 
the cluster nodes are attached to.

-g

Wolfgang Pauli wrote:
> Hi,
> 
> I am trying to setup gfs on a cluster that spans over two subnets. dream is a 
> node with to interefaces, one on each subnet. I thought the below setup 
> should work (taken from http://gfs.wikidev.net/Installation ). But it does 
> not. Can anybody tell me what is wrong with that?
> 
> cheers,
> 
> wolfgang
> 
> <?xml version="1.0" ?>
> <cluster config_version="2" name="alpha_cluster">
> 	<fence_daemon post_fail_delay="0" post_join_delay="3"/>
> 	<clusternodes>
> 		<clusternode name="dream" votes="1">
> 			<altname name"dream-e1">
> 			<multicast addr="224.0.0.1" interface="eth0"/>
> 			<multicast addr="224.0.0.9" interface="eth1"/>
> 			<fence>
> 				<method name="1">
> 					<device name="human" nodename="dream"/>
> 				</method>
> 			</fence>
> 		</clusternode>
> 		<clusternode name="neo" votes="1">
> 			<multicast addr="224.0.0.1" interface="eth0"/>
> 			<fence>
> 				<method name="1">
> 					<device name="human" nodename="neo"/>
> 				</method>
> 			</fence>
> 		</clusternode>
> 		<clusternode name="node1" votes="1">
> 			<multicast addr="224.0.0.9" interface="eth0"/>
> 			<fence>
> 				<method name="1">
> 					<device name="human" nodename="node1"/>
> 				</method>
> 			</fence>
> 		</clusternode>
> 	</clusternodes>
> 	<cman expected_votes="1" two_node="1">
> 		<multicast addr="224.0.0.1"/>
> 		<multicast addr="224.0.0.9"/>
> 	</cman>
> 	<fencedevices>
> 		<fencedevice agent="fence_manual" name="human"/>
> 	</fencedevices>
> 	<rm>
> 		<failoverdomains/>
> 		<resources/>
> 	</rm>
> </cluster>
> 
> --
> Linux-cluster mailing list
> Linux-cluster at redhat.com
> https://www.redhat.com/mailman/listinfo/linux-cluster
> 


-- 
Greg Forte
gforte at udel.edu
IT - User Services
University of Delaware
302-831-1982
Newark, DE