Online Deployment in Cluster

[Former Member]

Hello,

we have currently set up a Netweaver application server cluster on SLES10. The cluster is setup like this:

Two physical servers.

1 WebDispatcher

1 SCS

1 JavaCentral Instance with SDM

3 Dialog Instances.

We wanted to know if the SDM provides an online deployment possibility, in which the WebDispatcher recognizes which dialog instance is not available due to current deployment.

Does there have to be something configured in the SDM or WebDispatcher?

We want to ensure if we deploy something during runtime that the server handles this appropriately without timeouts or errors.

Regards,

Kai

[Former Member]

Ok, we have tested to set the refresh rate to 30 seconds. I have checked the availability during the deployment. It wasn't really satisfying.

Does the MessageServer know when an instance is currently receiving a new software (deployment going on) and then dispatches around this instance?

Can I setup this somewhere? Or is there a different procedure to ensure online deployment without any problems? Or offline deployment to put one instance down and deploy on the restart (of every single instance at one time).

Regards,

Kai

[michael_mulvey]

Hi Kai,

No the webdispatcher cannot be used by SDM to deploy software to other instances. The webdispatcher is used specifically to load balance HTTP, HTTPS and SMTP requests over different instances to one logical backend system.

This is not specific to SDM but the webdispatcher will poll the backend message server for specific information about the availability of all backend instances via the profile paraemeter wdisp/auto_refresh (default 120 seconds).

The information relayed from the message server includes the state of the instances. If the message server reports to the webdisp that a server is down it will be removed from the webdispatcher server pool.

Note: Dont set the wdisp/auto_refresh parameter too low as the webdispatcher uses this for receiving load balancing information as well as the state of the instances.

Hope this helps

Michael