[CURATOR-359] Curator can't connect to Read Only ensemble

The read requests fail when connecting to a read only ensemble.

I made a class for this using TestingCluster, but it requires to set iptables rules in order to mimic a real (remote) read-only ensemble. The test will do this:

1) start a TestingCluster

2) stop 2 of the 3 nodes

3) user has to run the iptables commands (specified in the logs)

4) a read request is issued every 3 seconds

All the read requests block for approx 2 minutes, then they all throw an exception (ConnectionLoss).

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Originally reported by benjamin.jaton, imported from: Curator can't connect to Read Only ensemble

• assignee: randgalt
  
• status: Open
  
• priority: Critical
  
• resolution: Unresolved
  
• imported: 2025-01-21
  

Start with the TestingCluster reproduction described in the issue and inspect the logs after stopping two of the three nodes and applying the listed iptables rules. Trace the read-request connection path and verify the behavior against a read-only ensemble. Done means read requests no longer block for minutes before failing with ConnectionLoss.

Written by the indexing model from the issue text.