2020-05-22T14:57:02.573+0000 I  CONTROL  [LogicalSessionCacheReap] Failed to reap transaction table: HostUnreachable: network error while attempting to run command 'ismaster' on host 'mongo-node-4:27017' 
2020-05-22T14:57:02.592+0000 I  NETWORK  [LogicalSessionCacheReap] Successfully connected to mongo-node-4:27017 (2 connections now open to mongo-node-4:27017 with a 0 second timeout)
2020-05-22T14:57:08.717+0000 I  NETWORK  [LogicalSessionCacheRefresh] DBClientConnection failed to receive message from -mongo-node-4:27017 - SocketException: Connection timed out
2020-05-22T14:57:08.717+0000 I  NETWORK  [LogicalSessionCacheRefresh] Detected bad connection created at 1590158176370506 microSec, clearing pool for mongo-node-4:27017 of 1 connections
2020-05-22T14:57:08.717+0000 I  NETWORK  [LogicalSessionCacheRefresh] Dropping all pooled connections to mongo-node-4:27017(with timeout of 0 seconds)
2020-05-22T14:57:08.717+0000 I  NETWORK  [LogicalSessionCacheRefresh] Ending connection to host -mongo-node-4:27017(with timeout of 0 seconds) due to bad connection status; 0 connections to that host remain open
2020-05-22T14:57:08.717+0000 I  CONTROL  [LogicalSessionCacheRefresh] Sessions collection is not set up; waiting until next sessions refresh interval: network error while attempting to run command 'ismaster' on host '-mongo-node-4:27017' 
2020-05-22T14:57:08.718+0000 I  NETWORK  [LogicalSessionCacheRefresh] Starting new replica set monitor for -rs/-mongo-node-3:27017,-mongo-node-4:27017,-mongo-node-5.k12tech.eu:27017,-mongo-node-6.k12tech.eu:27017