Hadoop cluster Datanode Dead or Secondarynamenode process disappearance processing method

When a problem occurs in a single node of a Hadoop cluster, it is generally not necessary to restart the entire system, just restart the node and it will automatically connect to the entire cluster.

Enter the following command on the necrotic node:

hadoop-daemon.sh Start Datanode

hadoop-daemon.sh Start Secondarynamenode

The cases are as follows:

Hadoop node crashes, can ping Pass, SSH Connection not on

Case:

Time: 2014/9/11 a.m.

Performance: tc-hadoop018 node on Hadoop web interface dead

Symptom: SSH connection to node tc-hadoop018 not on

Workaround:

Notify the computer room administrator to restart the machine,

Turn off firewall View status:/etc/init.d/iptatbles status closed:/etc/init.d/iptables stop

hadoop-daemon.sh Stop Datanode

hadoop-daemon.sh Stop Tasktracker

hadoop-daemon.sh Start Datanode

hadoop-daemon.sh Start Tasktracker

At this point, the startup succeeds

"Use caution" when necessary, view the Web interface and restart the entire cluster without running a job.

Hadoop the Secondarynamenode Port 50090 not through

Case:

Time: 2014/9/11 PM

Performance: Sos2 alarm prompt 123.125.244.6_50090 Port alarm

Symptom: JPS command 123.125.244.6 machine on Secondarynamenode process No

Workaround:

hadoop-daemon.sh Stop Secondarynamenode

hadoop-daemon.sh Start Secondarynamenode

At this point, the startup succeeds

Hadoop cluster Datanode Dead or Secondarynamenode process disappearance processing method