David Turner 0152c40724
Log when probe succeeds but full connection fails (#51304) (#51357)
It is permitted for nodes to accept transport connections at addresses other
than their publish address, which allows a good deal of flexibility when
configuring discovery. However, it is not unusual for users to misconfigure
nodes to pick a publish address which is inaccessible to other nodes. We see
this happen a lot if the nodes are on different networks separated by a proxy,
or if the nodes are running in Docker with the wrong kind of network config.

In this case we offer no useful feedback to the user unless they enable
TRACE-level logs. It's particularly tricky to diagnose because if we test
connectivity between the nodes (using their discovery addresses) then all will
appear well.

This commit adds a WARN-level log if this kind of misconfiguration is detected:
the probe connection has succeeded (to indicate that we are really talking to a
healthy Elasticsearch node) but the followup connection attempt fails.

It also tidies up some loose ends in `HandshakingTransportAddressConnector`,
removing some TODOs that need not be completed, and registering its
accidentally-unregistered timeout settings.
2020-01-23 17:27:59 +00:00
..