Server 1: NN1 and ZKFC1 Server 2: NN2 and ZKFC2
Server 3: Journal1 and ZK1 Server 4: Journal2 and ZK2 Server 5: Journal3 and ZK3 Server 6+: Datanode All in the same rack. I would expect the ZKFC from the active name node server to lose its lock and the other ZKFC to tell the standby namenode that it should become active (I’m assuming that’s how it works). - Dave From: Juan Carlos [mailto:juc...@gmail.com] Sent: Friday, March 14, 2014 9:12 PM To: user@hadoop.apache.org Subject: Re: HA NN Failover question Hi Dave, How many zookeeper servers do you have and where are them? Juan Carlos Fernández Rodríguez El 15/03/2014, a las 01:21, dlmarion <dlmar...@hotmail.com> escribió: I was doing some testing with HA NN today. I set up two NN with active failover (ZKFC) using sshfence. I tested that its working on both NN by doing ‘kill -9 <pid>’ on the active NN. When I did this on the active node, the standby would become the active and everything seemed to work. Next, I logged onto the active NN and did a ‘service network stop’ to simulate a NIC/network failure. The standby did not become the active in this scenario. In fact, it remained in standby mode and complained in the log that it could not communicate with (what was) the active NN. I was unable to find anything relevant via searches in Google in Jira. Does anyone have experience successfully testing this? I’m hoping that it is just a configuration problem. FWIW, when the network was restarted on the active NN, it failed over almost immediately. Thanks, Dave
