I'm seeing something a bit weird. In our environment we've upped the session timeout to 10 minutes. I see that the client connections successfully negotiate the 10 minute timeout. However I've seen a case where the client session gets timed out in 40s if it is unable to ever initiate the session. Is there a separate timeout somewhere?
Thanks, Martin Log excerpts below (unfortunately the server-side logs are not available): 2011-10-18 21:38:59,218 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread()-0] - Opening socket connection to server localhost/0:0:0:0:0:0:0:1:16015 2011-10-18 21:38:59,220 WARN ClientCnxn [ZooKeeperClientCnxn--SendThread(localhost:16015)-0] - Session 0x0 for server null, unexpected error, closing socket connection and attempting reconnect 2011-10-18 21:39:00,181 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread(localhost:16015)-0] - Opening socket connection to server localhost/127.0.0.1:16015 2011-10-18 21:39:00,184 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread(localhost:16015)-0] - Socket connection established to localhost/127.0.0.1:16015, initiating session 2011-10-18 21:39:00,241 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Session establishment complete on server localhost/127.0.0.1:16015, sessionid = 0x13319d4a8c3000c, negotiated timeout = 600000 2011-10-18 21:39:00,326 INFO ZooKeeper [main] - Initiating client connection, connectString=localhost:16015 sessionTimeout=600000 watcher=com.attivio.global.AieZooKeeper@45490eb5 2011-10-18 21:39:00,329 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread()-0] - Opening socket connection to server localhost/0:0:0:0:0:0:0:1:16015 2011-10-18 21:39:00,329 WARN ClientCnxn [ZooKeeperClientCnxn--SendThread(localhost:16015)-0] - Session 0x0 for server null, unexpected error, closing socket connection and attempting reconnect 2011-10-18 21:39:00,665 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread(localhost:16015)-0] - Opening socket connection to server localhost/127.0.0.1:16015 2011-10-18 21:39:00,666 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread(localhost:16015)-0] - Socket connection established to localhost/127.0.0.1:16015, initiating session 2011-10-18 21:39:00,670 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Session establishment complete on server localhost/127.0.0.1:16015, sessionid = 0x13319d4a8c3000d, negotiated timeout = 600000 2011-10-18 21:39:02,125 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Unable to read additional data from server sessionid 0x13319d4a8c3000d, likely server has closed socket, closing socket connection and attempting reconnect 2011-10-18 21:39:02,125 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Unable to read additional data from server sessionid 0x13319d4a8c3000c, likely server has closed socket, closing socket connection and attempting reconnect 2011-10-18 21:39:02,295 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Opening socket connection to server localhost/0:0:0:0:0:0:0:1:16015 2011-10-18 21:39:02,295 WARN ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Session 0x13319d4a8c3000d for server null, unexpected error, closing socket connection and attempting reconnect 2011-10-18 21:39:02,873 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Opening socket connection to server localhost/0:0:0:0:0:0:0:1:16015 2011-10-18 21:39:02,873 WARN ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Session 0x13319d4a8c3000c for server null, unexpected error, closing socket connection and attempting reconnect 2011-10-18 21:39:03,676 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Opening socket connection to server localhost/127.0.0.1:16015 2011-10-18 21:39:03,677 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Socket connection established to localhost/127.0.0.1:16015, initiating session 2011-10-18 21:39:03,678 WARN ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Session 0x13319d4a8c3000d for server localhost/127.0.0.1:16015, unexpected error, closing socket connection and attempting reconnect 2011-10-18 21:39:04,027 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Opening socket connection to server localhost/0:0:0:0:0:0:0:1:16015 2011-10-18 21:39:04,027 WARN ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Session 0x13319d4a8c3000d for server null, unexpected error, closing socket connection and attempting reconnect 2011-10-18 21:39:04,416 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Opening socket connection to server localhost/127.0.0.1:16015 2011-10-18 21:39:04,417 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Socket connection established to localhost/127.0.0.1:16015, initiating session 2011-10-18 21:39:04,417 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Unable to read additional data from server sessionid 0x13319d4a8c3000c, likely server has closed socket, closing socket connection and attempting reconnect 2011-10-18 21:39:04,705 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Opening socket connection to server localhost/0:0:0:0:0:0:0:1:16015 2011-10-18 21:39:04,705 WARN ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Session 0x13319d4a8c3000c for server null, unexpected error, closing socket connection and attempting reconnect 2011-10-18 21:39:05,447 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Opening socket connection to server localhost/127.0.0.1:16015 2011-10-18 21:39:05,448 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Socket connection established to localhost/127.0.0.1:16015, initiating session 2011-10-18 21:39:05,449 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Unable to read additional data from server sessionid 0x13319d4a8c3000d, likely server has closed socket, closing socket connection and attempting reconnect Lots more of those, then: 2011-10-18 21:39:39,387 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Opening socket connection to server localhost/127.0.0.1:16015 2011-10-18 21:39:39,388 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Socket connection established to localhost/127.0.0.1:16015, initiating session 2011-10-18 21:39:39,388 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Unable to read additional data from server sessionid 0x13319d4a8c3000c, likely server has closed socket, closing socket connection and attempting reconnect 2011-10-18 21:39:39,592 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Opening socket connection to server localhost/0:0:0:0:0:0:0:1:16015 2011-10-18 21:39:39,592 WARN ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Session 0x13319d4a8c3000d for server null, unexpected error, closing socket connection and attempting reconnect 2011-10-18 21:39:39,735 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Opening socket connection to server localhost/0:0:0:0:0:0:0:1:16015 2011-10-18 21:39:39,735 WARN ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000c] - Session 0x13319d4a8c3000c for server null, unexpected error, closing socket connection and attempting reconnect 2011-10-18 21:39:41,400 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Opening socket connection to server localhost/127.0.0.1:16015 2011-10-18 21:39:41,401 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Socket connection established to localhost/127.0.0.1:16015, initiating session 2011-10-18 21:39:41,402 INFO ClientCnxn [ZooKeeperClientCnxn--SendThread-13319d4a8c3000d] - Unable to reconnect to ZooKeeper service, session 0x13319d4a8c3000d has expired, closing socket connection
