We have an ECS cluster with 4 services, where each task joins a single cluster, via discovery ECS discovery service.

Currently when I deploy, new tasks will attempt to join the old cluster as they a being brought up (potential red flag). I think (but not sure) that this is causing the above message to happen a lot on deploy, as once new tasks reach a healthy state, old tasks drop off causing incomplete partitions as some tasks may be notified first.

This is causing many issues, especially with Horde as it tries to connect to the old nodes (something between Libcluster and Horde not communicating correctly) resulting in every deploy having our Horde registry be reset and orphaned processes.

I’m not sure if this is actually the issue though or not or if there is something else I’m missing. I’m using LibCluster DNSPoller (1 second interval) for node membership and OTP 26.

My questions are:

1. Is this expected for this setup (dynamic cluster with nodes joining / leaving frequently) or am I missing something?
2. I couldn’t find a concrete answer on this, but is it better to have the new nodes not join the old cluster when they are brought up (e.g. ensure they all have the same version etc.)?