This post is part of a series exploring the unique aspects and capabilities of WebSphere Liberty when running on z/OS.
We'll also explore considerations when moving from WebSphere traditional on z/OS to Liberty on z/OS.
The next post in the series is here.
To start at the beginning, follow this link to the first post.
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So far in this series we’ve talked about having multiple Liberty servers that you might want to separate into different groups of servers based on administrative control or lines of business or some other non-technical thing. But you might also have Liberty servers that are underneath other software products, or running inside some other thing (e.g. CICS).
Suppose you have something like the following environment. You’ve got 10 Liberty servers running five different applications, two servers for each application. You’ve got another 10 servers running z/OS Connect. You’ve got one server underneath z/OSMF. And then there are a bunch of other servers running inside various CICS regions.
First of all, should you mix all these things together? Probably not. The products like z/OSMF and z/OS Connect will be happier if their configuration and output directories are separate from each other. And the CICS servers are probably managed by an entirely different group from any of the others. So right away you’ve got a few different groupings.
z/OSMF has probably got its own separate environment all to itself. It is using the copy of Liberty embedded in z/OS also, which is probably not the same as anything else (unless you have other IBM products that also use it). Keep its configuration and output away from everything else. It might also be managed by the ‘z/OS folks’ which might not be the same as the ‘app server folks’.
The z/OS Connect servers are probably also managed by somebody separate. Perhaps if it all front-ends things in CICS it is managed by the CICS folks. Or perhaps not. Politics are probably going to influence how these are organized, and I’d look to the z/OS Connect product itself for guidance about how (or if) to group them.
Liberty-in-CICS servers are probably managed by the same group that manages the CICS servers already. Let them do their own thing.
And your ten plain old Liberty application servers? You could put all ten together, or break them up into groups by application (maybe some of the applications go together while others go with other groups?).
But…having done all this separation..should you share configuration? After all, if the CICS servers need a datasource definition to DB2 and so do the stand-alone Liberty servers should it be in one place and shared? Or do you think of those separately and it is possible one might need to change when the other doesn’t?
To a certain extent the amount of separation will depend on how separate these different groups actually are. If the ‘CICS folks’ and the Liberty administrators for the stand-alone servers are really just two different people in the same office, maybe you don’t need as much separation as if they are two different departments of people located three time zones apart.
Ultimately there’s a lot of politics involved, but I think fundamentally these are separate things and should at least be kept a little separate.