Regarding logon load balancing when removing AS from logon group

[Former Member]

Hi All,

I have a requirement where I need to shutdown my App Server. But for this i would have to make sure that i do in such a way that it does not cause any downtime for whole of the system (which includes CI+ 9 App servers to it).

As per my understanding would it be right to remove this App server from logon group 24 hrs before my downtime of this AS, so that no new jobs get triggerred on this AS and also no dialog logon occurs. Let me know if my thinking is correct.

Can it happen that during these 24 hours when AS os removed from logon group new jobs may still get triggered on it since message server still would be knowing about the presence of this app server (all app servers are still visible in SM51).

Please help me in this regard and let me know the best approach

Regards,

Ashish Robinson

[Former Member]

Ashish V Robinson ,

Please Contact you Job scheduling team to find out what process thee are following to schedule a jobs & how it works

and also find any of the user is loggin into that perticular AS by adding the entries in GU like SID ,System number .....

Thanks

Kiran.GVL

[Former Member]

Taking out from Logon group will only work for Dialog user for batch process check :

SAP Note 786412 - Determining execution server of jobs w/o target server.

Also make sure that you remove the sever out from RFC server Group (RZ12). Hopefully none of the RFC's are directly pointing to this app server or no batch jobs are defined which have target server specified as this app server in it.

Hope this helps.

Thanks,

Naveed

[Former Member]

Hi Naved and Subhash,

Thanks for you replies, but my querry is still not answered for me. I need to understand that when you are removing an app server will any new jobs ger routed to this server, please note thta in my scenario jobs get triggered from TWS tool and not from SAP, TWS would trigger the scheduled job in SAP at a particular pre-defined time, so i need to understand that in this case as a particular App server is not chosen but accordingly any one is chosen which is present in logon group. So if i am removing my concerned AS from logon group (aslo from RZ12) then woudl it still happen that jobs at random could get scheduled on this AS!

Please let me know on this.

Thanks & Regards,

Ashish Robinson

[Former Member]

Not sure about TWS. We use Redwood/CPS and after defining SAP_DEFAULT_BTC, the Jobs are triggered only on the servers that are assigned to this Server group.

The other thing that you can do if you are not sure is to put all the batch process of that app server in Stop Mode. You can do that from SM50. This will make sure that no background job runs on that server.

Thanks,

Naveed

[Former Member]

Hi Naved,

Thanks. Could i do like by reducing all my background WPs to 0 via RZ04 in operation mode for this APP server so i suppose this would prevent any new job getting triggered on this server then.

Thanks

[Former Member]

That is another very good option. Never tried it but sounds good.

Thanks,

Naveed

[Former Member]

This wouldn't do any good until you perform this below step:

RZ03 --> SELECT APP SERVER --> SWITCH OPERATION MODE --> SELECTED SERVER TO DAY/NO BTC MODE

Check SM50 to see if there are NO BTC.

Thanks

SM

[Former Member]

Hello Ashish,

Removing app from SMLG will help in user not getting dialogue work processes on that app server.

Then in SM61select that application server and edit the job starter option for that application server which will help in not starting any background jobs on that server.

Again if there are already users they will still be on system and jobs which are already active they still run but new users and new jobs will not be able to access the system.

Using TWS you should be able to control on which application server you want to run the background jobs though.

Regards

Vivek

[Former Member]

Hi vivek,

Removing dialog server please follow below beofre your actual downtime start:

1)From SM61(Job scedhular) remove old group and create new group and dont include that dialog server which you want to shutdown.

2) Remove the sever out from RFC server Group (RZ12)

3) Removing application (dialog) from logon group

4) Reducie all background WPs to 0 via RZ04 in operation mode for this APP server

Hope this will help you.

Thanks

Deepak R Patil

[Former Member]

Hi vivek,

Regarding tivoli job scheduling .

While defining the job , If you explicitly mention the target server as the AS (hat you are going to remove) then there would be a problem.

In general case , whenever people define the jobs in Tivoli , they use the target host (not target server). so based on the availability it goes on to the Application server which is free.

It would be better if you cross-check with your TWS team to get the list of such jobs.

Regards

Sandeep

[former_member185031]

If you will remove the App Server details from Logon Group then no body will be available to login into App server through Load Balancing. So you can easily shut down the App Server. But Before shutting down the server make sure that no backgrund jobs has been Scheduled to start on that server. If anyone Schedule a new job and define the specific App server over there then it will be Schedule to run specific server. You have to check it manually.

Regards,

Subhash