JBoss Standalone or Domain
From my understanding, Pega does not use JBoss HA features (eg. session replication). For our project, we will have 2 JBoss instances running from 2 different servers (VMs). Like to know what is the recommendation between the below 2 options:
- Deploy Pega on 2 standalone JBoss servers or
- Deploy Pega on 2 JBoss servers belonging to a single managed domain
We are okay with deploying same Pega patches on different standalone servers but we have concerns if we need to start the different VMs in certain sequence during OS patching.
***Edited by Moderator Marissa to update platform capability tags***
Pegasystems Inc.
IT
Hi Josiah that's correct: Pega has it's own HA feature which is Application Server (AS) independent as such AS Session Replication is not used.
That said with JBoss both modes (standalone and domain) are supported.
Feel free to choose the mode that suits best your requirements.
IMHO it is simpler to use standalone mode when you have to deal with few nodes. Domain mode makes sense when many nodes are used.
Very few hotfixes (hybrid) and changes to application deployment descriptors (e.g. when deploying a custom MDB) require application redeployment. In that case domain mode can save some time.
I don't get how the latest point "...we have concerns if we need to start the different VMs in certain sequence during OS patching." is related to standalone or domain mode. Can you please clarify?
Kind Regards,
Domenico
Ncs Pte Ltd
SG
Hi Domenico,
Thank for the info.
The concern for "...we have concerns if we need to start the different VMs in certain sequence during OS patching." is for JBoss Domain mode.
My understanding is the VM with JBoss domain controller must always start first and we may risk downtime if the OS patching engineer did not perform the VM restart in the proper sequence.
Best Regards,
Josiah
Pegasystems Inc.
IT
Hi Josiah,
thanks for the clarification. Now I understood your concern.
Actually there is some additional complexity in domain mode but I assume it shouldn't be a big issue as long as maintenance is performed following previously tested procedures.
Best,
Domenico