Need help in capturing event when an node leaves or joins cluseter

[dukechandu]

HI,

Need help in capturing event while node joining/leaving cluster , to send an email, can any one give me an idea whether do we have any event listeners to capture joining and leaving node ?

Thanks in advance

[wdfink]

A simple way is to use the logfile.

You might use log4j and filter the cluster messages for "New cluster view" and send an email.

Another option is to use an external process to watch the logfile and filter the message.

[dukechandu]

thank you for the responce

[pferraro]

There are ways to detect this programmatically, but I'm not sure which version of AS/WildFly you are using.  In WF9, the easiest way to do this is to leverage the public clustering API.

e.g.

@Startup
@Singleton
public class MyViewChangeDetector implements Group.Listener {
    @Resource(lookup = "java:jboss/clustering/group/default")
    private Group group;

    @PostConstruct
    public void init() {
        this.group.addListener(this);
    }

    @PreDestroy
    public void destroy() {
        this.group.removeListener(this);
    }

    @Override
    public void membershipChanged(List<Node> previousMembers, List<Node> members, boolean merged) {
        // Send email
    }
}

... where "default" refers to the default channel of the node (as defined by the jgroups subsystem configuration).

[dukechandu]

HI,

i am using jboss 6.2 eap , jgroups 3.2 with java and not using wildfly package.

using ehcache, which will take jgroups.xml as paramater, and forms cache.

do we have anything similar implementation with jgroups.jar ?

Thanks in advance

[pferraro]

Probably the easiest way to do this pre-WildFly is to use Infinispan directly.

e.g.

@Startup
@Singleton
@Listener
public class MyViewChangeDetector {
    @Resource(lookup = "java:jboss/infinispan/container/server")
    private EmbeddedCacheManager manager;

    @PostConstruct
    public void init() {
        this.manager.addListener(this);
    }

    @PreDestroy
    public void destroy() {
        this.manager.removeListener(this);
    }

    @ViewChanged
    public void viewChanged(ViewChangedEvent event) {
        // Send email
    }
}

[dukechandu]

you are suggesting to use Infinispan jar files ?

i don't know the difference or advantages of jgroups with Infinispan, is jgroups and Infinispan both are different or alternative implementation of jgroups ?.

i am just using jgroups and replicationcache.

Thanks

[pferraro]

You don't need to add any jar files to your application.  Just export the relevant org.infinispan module to your application.

See: Class Loading in WildFly - WildFly 8 - Project Documentation Editor

In EAP6, the transport of an Infinispan cache manager uses a JGroups channel.  In other words, one is a building block of the other.

[dukechandu]

we are using Replcated Caching Using RMI, you are suggesting in stead of RMI cache , if we use Infinispan cache maanger it will work,.

Thanks for the response, i will go through documentation once.