It's all about the answers!

Ask a question

Distributed CLM 4.0 : Moving from Tomcat to WAS

Ketut Mahaindra (1333) | asked Mar 18 '13, 3:11 a.m.

Dear all,

We have a distributed deployment of CLM 4.0 (DB, JTS, RRC, RTC, RQM each on a dedicated server). The deployment is currently setup using the bundled Apache Tomcat that comes with the installation package. We are in need to make a migration from Tomcat to WAS 8.0 because we would like to have the single sign-on feature as well as the ability to deploy RRDI later on.

I would like to get an advice if anybody has done this type of migration before. What are the things that we need to take care? Can we migrate each of the server one by one, or does it have to be done in a single shot? Instead of migrating, can we simply install a new server instance with WAS instead?

Any advice are appreciated. Thanks in advance for your kind attention.

Pavithra Kasturirangan commented Mar 18 '13, 3:36 a.m.

 I'm interested in this topic as well.

Is there any known limitation or important points to be considered during this migration? Let us know if there is any article on the migration procedure already available.
It would be great if someone could share the migration experience on the forum

Ketut Mahaindra commented Mar 18 '13, 3:41 a.m.

Hi Pavithra,

Good to hear other people are looking to this too. I will post what we experience later when we took the "path". I am collecting as much information as possible first, and I am hoping to get the help from the forum too. :)

One answer

permanent link
Ralph Schoon (62.9k33645) | answered Mar 18 '13, 3:33 a.m.
Hi Ketut, talks about this. The Administation Workshop goes through this as well.

If you talk about a distributed deployment, we refer to this term if the applications are deployed on different servers. You would have to make sure that you keep the public URI of the servers. You should be able to upgrade one application at a time if it really is distributed.

Ralph Schoon commented Mar 18 '13, 3:34 a.m.

You would have as many WAS instances as you have tomcat instances today.

Ketut Mahaindra commented Mar 18 '13, 3:38 a.m.

Hi Ralph,

Thanks for the pointer, I will have a look.

A quick question, what will happen to  the user authentication when we have a mixed of Tomcat and WAS in the deployment when we migrate one application at a time?

Ralph Schoon commented Mar 18 '13, 3:47 a.m.

Hi, I would assume you would have to log in several times. IBM HTTPS/WAS single sign on only works on WAS and not towards Tomcat.

Sterling Ferguson-II commented Mar 18 '13, 9:13 a.m.


I have a quick question on this topic as well. I just looked at the workshop, we have an instance where someone is moving from tomcat/derby to WAS/DB2,(future RRDI). They have 2 machines. If CLM is on one, and DB2 is on the other, where do you recommend RRDI go? If it goes on to the same machine as DB2, where does WAS go? Do we need one or two WAS instances?


Ralph Schoon commented Mar 18 '13, 9:30 a.m.

Sterling, if you only have just these two machines I would
- Move to WAS on the machine where you had Tomcat installed. How much profiles you need is determined by your public URI.
- If you have just one common public URI (including port) you can use IHS (IBM HTTP Server) as reverse proxy. That will allow you to spread to more machines later.
- The RRDI Database goes on the DB server. You could mix that with RRDI+WAS, but that would have impact on the DB performace, so I wouldn't.
- So RRDI goes to any other server. Initially to the App Server machine that has WAS on it. RRDI wants 8 GM memory minimum, so I would plan to have enough for all applications. Monitor your resources on the machine. Run JazzMon. I would regardless of having CLM and RRDI on one machine or not.

I would assume that sooner or later you need more memory on the Application server machine if you host CLM and RRDI on one machine. To increase performance it might be a good idea to distribute the applications to more servers, which is now possible behind IHS, if you see the machine hits its limits.

Your answer

Register or to post your answer.