Problem fetching assets: Get : unsupported protocol scheme ""

Had an discussion in Slack with @dxiri concerning the error message that showed up in an event output.

error getting assets for event: error fetching asset: Get : unsupported protocol scheme ""

Real quick solution, upgrade your agent to match the backend version you are running.

Thought it would be good to summarize what’s happening.

You may see this error msg show up in your events if you have old agents running checks that try to use multi-build styled assets. Multiple build capable assets were introduced in Sensu Go 5.13 and bonsai default asset definitions transitioned to make use of multi-build support some time after.

If you are running an agent older than 5.14 with newer backends at this point, you may have some head scratcher problems with asset fetching.

So if you are seeing asset fetch errors, do a quick check to make sure your agent version matches your backend version.

In fact…
now that I think about it… there’s a good opportunity to write a couple of new Sensu plugins to help users stay on top of this.

  1. sensuctl command plugin, that an admin can run from their workstation that will report outdated agent entitites based on the entity info
  2. sensu check plugin, that will do similar but will alert you if any agents are found to be below allowed version.