Commits on Sep 11, 2020

1. kvserver: address migration concern with node liveness …

   In cockroachdb#53842 we introduced a change to always persist a liveness record on
   start up. As part of that change, we refactored how the liveness
   heartbeat codepath dealt with missing liveness records: it knew to fetch
   it from KV given we were now maintaining the invariant that it would
   always be present. Except that wasn't necessarily true, as demonstrated
   by the following scenario:
   
   ```
   // - v20.1 node gets added to v20.1 cluster, and is quickly removed
   //   before being able to persist its liveness record.
   // - The cluster is upgraded to v20.2.
   // - The node from earlier is rolled into v20.2, and re-added to the
   //   cluster.
   // - It's never able to successfully heartbeat (it didn't join
   //   through the join rpc, bootstrap, or gossip). Welp.
   ```
   Though admittedly unlikely, we should handle it all the same instead of
   simply erroring out. We'll just fall back to creating the liveness
   record in-place as we did in v20.1 code. We can remove this fallback in
   21.1 code.
   
   Release note: None

   

   irfansharif committed Sep 11, 2020
   Configuration menu

   • View commit details
   • Copy full SHA for b394338
   • Browse repository at this point

   Copy the full SHA

   b394338 View commit details

   Browse the repository at this point in the history