JBoss AS 5.1 Cluster Deploy Questions

[welsh]

Hey,

I've been reading through documentation about the deploys that are available for deploying to the JBoss cluster, and I've only found the two deploy options:

• Farm Deploy
• HASingleton Deploy

And from what I understand of the HASingleton Deploy method, is that its only running the service on one Node (Master) while the rest of the nodes are in stand by mode incase the master goes down and they are now elected. This isn't perticuarly useful to me.

This leads me onto Farm Deploy, which will sync up the farm directory amongst all cluster members which is useful, however I have a couple questions that I need clarifying if possible.

1. With this method, is the Farm Deploy method sequentually or concurrently amonst all the nodes. Such that once one node is updated, does it update node 2, 3 and 4 at the same time or does it do node 2 and once thats done, do node 3, and once thats complete do node 4. If it is concurrently by default, is there a way to make it sequentually?
   
   
2. When the sync is occuring amongst the nodes, does the application go offline during this process or does it only go offline once the sync has finished and the restart is necessary?
   
   
3. Are these the only two methods of deploying to a clustered JBoss environment?

Any help with all of these would be great.

Thanks!

Welsh

[rhusar]

Hey!

Actually, farm has not much to do with clustering, you could also farm a stateless non-clustered application, its just a method of deploying on all hosts.

With this method, is the Farm Deploy method sequentually or concurrently amonst all the nodes. Such that once one node is updated, does it update node 2, 3 and 4 at the same time or does it do node 2 and once thats done, do node 3, and once thats complete do node 4. If it is concurrently by default, is there a way to make it sequentually?

I am not sure here, IIRC there were some Farm deployment strategies, you could check that. But I think it will redeploy as soon as it gets the updated web app from the other server and just redeploy it. This might not be optimal if you dont want any outage.

When the sync is occuring amongst the nodes, does the application go offline during this process or does it only go offline once the sync has finished and the restart is necessary?

Its standard redeploy so it does go "offline".

Are these the only two methods of deploying to a clustered JBoss environment?

Well, I wouldnt recommend any of these options (unless you want HA-Singleton which is a different story). Just use standard deploy mechanisms (copy to server/all/deploy/) and make sure the application is <distributable/>.

If you are looking for upgrade without outage, you might wanna take a look at mod_cluster and session draining.

HTH,

Rado

[wdfink]

In addition to what Radoslav Husar said, if you want have such control of deployment management you might have a look at AS7.1 which provide a poweful domain management including CLI and batch scripts for this.

For AS5 you might use JON (JBossON) for monitoring and management.

[welsh]

Hey,

Thanks to both of you for the responses which helped answer some questions but I have a quick follow up question.

Is there any reference material that you would recommend (Books, sites, articles, or etc.) for JBoss AS 5.1 (Unable to go to AS 7.1) in terms of tuning, setup and management?

Cheers,

Welsh

[rhusar]

Check the extensive product documentation here http://docs.redhat.com/docs/en-US/JBoss_Enterprise_Application_Platform/index.html however there might be certain differences with your community AS 5.1.

[wdfink]

JBoss in Action - Manning http://www.manning.com/jamae/

JBoss performance tuning http://www.amazon.com/JBoss-AS-5-Performance-Tuning/dp/184951402X

Also you will find a lot of wiki pages here in the community, don't stick on 5.1 because some 4.x articles might also be helpful

[welsh]

Hey,

Thanks for the links to the reference materials, looks like it will all provide a good amount of help to me.

Cheers

Welsh