Article Number
000031538
Applies To
RSA Product Set: Security Analytics
RSA Product/Service Type: MapR Warehouse (SAW)
RSA Version/Condition: 10.4.x, 10.5.x
Platform: CentOS
O/S Version: EL6
Issue
The wrong hostname on the loopback interface can cause problems creating the mapred volumes in the Security Analytics Warehouse (SAW).
When attempting to create the volume, the error message below will be logged.
2015-08-11 11:24:48,700 ERROR org.apache.hadoop.mapred.TaskTracker: Can not start TaskTracker because org.apache.hadoop.util.Shell$ExitCodeException: Failed to create local mapred volume.
Resolution
It is common to have a wrong hostname configured on the appliance.
To confirm this, issue the command below.
[root@rsa-saw-002 ~]# getent hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
127.0.0.1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.16.10 rsa-saw-001
192.168.16.11 rsa-saw-002
192.168.16.12 rsa-saw-003
If you do not get the expected output from the hostname command or the getent command, correct the host and DNS settings on the node.
A common problem is an incorrect loopback entry (127.0.x.x), which prevents the correct IP address from being assigned to the hostname.
