How does hadoop decide what its nodes hostnames are?
- by Dan R
Currently the urls generated by the jobtracker & namenode return either hostnames like bubbles.local or just bubbles. These end up not resolving unless the client machine has specified these in their /etc/hosts file.
When I run the hostname command on these machines it returns a hostname complete with the domain (E.G bubbles.example.com)
Running a small java test on these machines
InetAddress addr = InetAddress.getLocalHost();
byte[] ipAddr = addr.getAddress();
String hostname = addr.getHostName();
System.out.println(hostname);
Produces output just like the hostname command.
Where else could hadoop be grabbing a hostname to use in its jobtracker / namenode UI?
This is occurring in clusters with
Hadoop 1.0.3 and 1.0.4-SNAPSHOT from early august.
The machines are running CentOS release 5.8 (Final).
The generated URLs I'm referring to are like this
http://example:50075/browseDirectory.jsp?namenodeInfoPort=50070&dir=/
or
http://example.local:50075/browseDirectory.jsp?namenodeInfoPort=50070&dir=/
