Last rebuild failed - source refresh timeout
We are getting this error when we tried to reindex our prod instance. We are using Coveo for Sitecore version: 4.1.414.9, Sitecore version: 8.2.160729. For now, we only need to re-index a section of content tree. I reviewed https://docs.coveo.com/en/541/coveo-for-sitecore-v4/rebuilding-a-search-index Re-Indexing Only a Section of Your Content Tree Manually, is this approach suggested for a prod CD instance. Is this resource consuming process? I am asking this because our dev server was down when I tried this approach (I am not completely sure whether this caused the issue though).
It really depends, we need to see your log to be more precise.
But if I had to guess, I'd say that there is one or more Sitecore item which can't be processed on the Coveo Cloud Platform during the rebuild.
And since the Sitecore rebuild makes sure that every single indexed item is searchable at the end of its execution, and wait for 1 hour of inactivity on the Cloud Platform to really fail, that could be causing your timeout.
But again, that's just a blind guess.
Grab those log files and we will be more in a position to help you.