[HADOOP-13005] if local hostname doesn't resolve, HttpServer2 fails with a kerberos exception

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 2.7.2
• Component/s: net

Environment

a VM whose hostname was no longer in /etc/hosts

• Assignee: Unassigned
• Reporter: Steve Loughran
• Created: 06/Apr/16 10:29
• Updated: 15/Nov/18 21:27

Description

When a service (NN, DN) is started and the local hostname isn't in /etc/hosts, things will, obviously, fail.

However, the failure is reported as a wrapped Kerberos Exception, rather than going via the NetUtils.wrapException handling code java.lang.RuntimeException: Could not resolve Kerberos principal name: java.net.UnknownHostException: xubunty: xubunty: unknown error

The text is a dangerous distraction from the real cause. Especially as it appears even on systems which aren't running kerberos.

A fail-fast check could go into the http server startup process ahead of the security setup; NetUtils could add special reporting of the unknown-local-host problem