TFS 2015 Build Agent Update

Question

I would like to upload to my TFS 2015 some of the build tasks that are available here https://github.com/Microsoft/vso-agent-tasks . I have a problem with a specific task, since they require a minimum version of the agent of 1.89.0. My build agents are version 1.83.2. Now, the question is, how do I update my agents for this pool? If I right-click on the agent pool in my TFS and select the update all agents option, nothing will happen. I suppose because the latest version of my agent available in TFS is 1.83.2. Where can I find the latest version and how to update it?

Note. I am working on the premises of TFS 2015, not VSO.

thanks

Answer 1

If you right-click the agent pool and select Update All Agents, it will upgrade the agents to the local TFS server version. For example, if you initially installed some RC and later upgraded the server to RTM, some agents might have a lower version. Otherwise, as you mentioned, nothing will happen, because all agents are updated.

VSO has a different release model, and updates / patches for its agents are constantly being delivered. This is why the version is constantly growing.

It would be technically possible to get the source code of the latest VSO-agent tasks and send it to the local version of TFS 2015. However, it is considered an anti-pattern and the behavior is undocumented and unsupported.

Let me quote the assembly of vNext developers from this discussion (see the bottom of the topic):

This is not supported. It is very likely that the agent we in VSO will not work with the pre-server. You must use the version of the agent that comes with your server.

and

Undefined / untested behavior. It may work, maybe not. Design for agents to get pulled forward through the automatic update process downloaded from your service. The automatic update process can configs / layout on disk, whatever. This future agent may call REST apis, which are not, etc. The focus is on agents ahead, so that they can lazily update (using the minimum task agent demand, when restarting, or ultimately scheduled task).