Enterprise Portal DB Server Failover

[jonathan_yun]

Hi,

Our EP environment consists of the following hardware components:

(1) The SAP WAS JAVA resides on 5 LINUX hosts running on VMware (clustered), which can be moved to or restarted on a different cluster. All the host names will be preserved.

(2) The DB for the EP system resides on an AIX host which has failover capability via EMC's SRDF, but with a different host name during failover mode.

The problem we face now is that during the failover mode for the AIX host (DB server), how and where do we reconfigure the 5 portal hosts to point to the DB on a different AIX host than what it was initially installed on?

We tried manually changing the hostname in the default and instance profiles for the SAP WAS JAVA side, but the portal is still looking for the DB on the original host.

Anyone has experience with this or any helpful pointer would be greatly appreciated.

Thanks,

Jonathan Yun

[Former Member · Accepted solution]

I believe that "officially" SAP expects you to perform a system copy for the Java instances when you change the hostname of the system (either application instance or database server).

However... you did't mention what release your EP is but if it is 6.40 or 7.00 (7.01 probably still the same) please have look at SAP Note#757692, specifically at points 2 (3.2 & 3.3) Yeah the note has strange numbering!

i.e.

Adapt Secure Store Properties:

Start the config tool

It will complain that the connection to the database cannot be established, just choose OK to start the config tool.

Choose the secure store and update the parameter for jdbc/pool/<SID>/Url to replace the old with new database name. Apply & Save the changes.

Also check the other points in the note, but if I remember correctly this was all that I had to do in addition to the changing the default profiles etc. & environment variables (of <sid>adm user).

I have successfully used this note for the J2EE part of a BI 7.0 dual stack (ABAP+J2EE) system on AIX when the database was moved.

Also, I assume that you are changing the DB hostname from what was used for the installation to the virtual hostname that is now used in the failover scenario? (i.e. this will be a one-off change).

Thanks.

[jonathan_yun · Accepted solution]

Hi Colin,

Thank you very much for the information. We are in the process of creating the DB on a different host for our sandbox system to test and document the procedure. I will let you know how it goes once we finish with the testing.

BTW, we are on NW 7.01 SP7.

Thanks,

Jonathan Yun

[jonathan_yun]

Hi Colin and Sunny,

I want to thank both of you for the information you provided me. I was able to successfully complete my testings and the results were all positive.

Thanks again for the help.

Jonathan Yun

[sunny_pahuja2]

Hi,

You can avoid this situation only if you install your DB on virtual host so that when DB failover from one node to other then hostname will not change. As for Portal systems, lot of parameters points to hostname in different files like one resides in config tool (instance.properties file).

Thanks

Sunny

[jonathan_yun]

Hi Sunny,

Thanks for your reply and information.

During the recent SRM and PI installations, I noticed that sapinst offers to install the system on a "virtual host". We didn't choose to do that because all of our systems are running on virtual environments (AIX LPAR and LINUX VMware). My understand about the "virtual host" that sapinst offers is that it provides a level of abstraction from the physical host for all the configurations. It allow an installed system to be moved from host-a to host-b without or with minimal changes required. In simple terms, it is like a place holder for a real host that the system is going to be installed and run on. This place holder is going to be resolved into a physical host somehow and this is the part that I do not know. Would you please enlighten me? Any information wrt changing an existing system to use "virtual host" would be greatly appreciated.

Thanks,

Jonathan Yun

[sunny_pahuja2]

Hi,

Please check below guide on how to achieve virtual host configuration:

http://www.sdn.sap.com/irj/sdn/go/portal/prtroot/docs/library/uuid/e0f384d0-b8bf-2b10-3f9b-d7f7b70d0...

If you install a ABAP only system in HA configuration then it does not require virtual host configuration but in case of java it is required because Java system use host name reference on a number of places. So, its become difficult to start the system when host name changes on both the nodes.

Thanks

Sunny