Handling Failover for Lotus Server Agent

HCL Domino Domino Forum
1

Hi,We have written a Server agent in Java to synchronize contacts/ tasks data from users’ mailbox with our application database.

The agent will run on the server and process mailboxes of multiple users every hour.

The Domino server is in a cluster configuration with 1 main server and a backup server. In case of a failover scenario (1. the main server has gone down OR 2. Has exceeded a specific usage limit), the Lotus Users are automatically diverted to the backup node and continue accessing their mailboxes. The main node and backup node have a replication scheduled to sync the mailbox data for all the users.

What we are trying to acheive is - in case a failover occurs, our agent must also continue running on the backup server, and once the main server is back, it should stop running on the backup node and again start on the main server node.

  1. Are there any known ways of handling such failover scenarios for Server Agents?

  2. Handling case 2 (where the main server only becomes slow, but is still running) , is adding a lot of complexity. Should we try to handle this scenario in our design?

Any inputs/ suggestions are greatly appreciated.

Thanks,

Sameer

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Subject: Failover for agents

The basic idea is:

  1. Your agent should be scheduled to run on - Any Server -

  2. Add some code at the beginning that checks on what server it runs (master or failover).

  3. If it runs on master nothing special to test, let it run.

  4. If it runs on failover, check if master server is alive. If no, let it run, if yes, exit.

Notice that as always this won’t work if the network link betweek the 2 servers is down.

Thierry Cayla

http://dominoeffects.serveblog.net