Good practice – Use the rolling upgrade option when you update IBM BPM

This came up in a Sametime chat earlier today …

In the context of an IBM BPM 8.5.6 Cumulative Fix update, which do we upgrade / patch first - Process Center or connected Process Server(s) ?

I thought - and was correct - that we should always start with the Process Servers before patching the Process Center.

My Polish colleague who has a mother who bakes exceedingly good cakes,  M, confirmed this: -

Good practice – Use the rolling upgrade option when you update IBM BPM

…

If you install IBM® Business Process Manager (BPM) fix packs V7.5.1.2, V8.0.1.2, V8.5.0.1, or upgrade to V8.5.5 or V8.5.6 from V8.5.0.1 or V8.5.5, you can use the rolling upgrade option. By using the rolling upgrade approach, you can incrementally upgrade one process server at a time, starting with test, then staging, and finishing with production. The final step is to upgrade your IBM Process Center and desktop tools.

…

It's worth also remembering that, very often, when one applies a major update ( Cumulative Fix, Fix Pack or Upgrade ) to Process Center, then the Process Designer tool MAY also be updated ( the release notes for the fix pack / upgrade will confirm this ).

Therefore, there's a good likelihood that your developers will need to download new copies of Process Designer, from Process Center once it's back up-and-running, and then reinstall PD on their desktops.

If you've only got one Process Center and lots of developers, this may well be an issue.

On a previous project, we mitigated this by patching our Sandpit environment to EXACTLY the same level as the Development environment, up-front, thus proving the patching strategy / approach. We then downloaded the updated Process Designer, tested that it connected to the Sandpit, and then shared the PD .ZIP file with our 60+ developers, many of whom were off-shore, via a different channel ( a secure file-share ).

That way, the developers could install the new copy of PD ( into an alternate directory ), wait until the Development environment was patched and back on-line, and then test new PD to "new" PC.

Once they were happy, they could uninstall the old PD ….

For the record, this also validated the approach: -

Performing a rolling upgrade

…

You can roll out maintenance incrementally in an IBM® Business Process Manager installation that consists of a Process Center and multiple Process Servers, allowing for the continued running of production applications during the upgrade and regression test period....
To perform a rolling upgrade, upgrade first the Process Servers and then the IBM Process Center and tools.
Note: A rolling upgrade can be performed only when applying fix packs, refresh packs, or interim fixes. It cannot be used for migration between major releases.

…