[HADOOP-6682] NetUtils:normalizeHostName does not process hostnames starting with [a-f] correctly

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.22.0
• Component/s: io
• Hadoop Flags: Reviewed
• Assignee: Jakob Homan
• Reporter: Jakob Homan
• Created: 05/Apr/10 23:54
• Updated: 12/Dec/11 06:19
• Resolved: 12/Jun/10 02:12

Description

public static String normalizeHostName(String name) {
if (Character.digit(name.charAt(0), 16) != -1) {
return name;

This code is attempting to short-circuit the hostname->ip resolution on the assumption that if name starts with a digit, it's already an ip address. This is of questionable value, but because it checks for a hex digit, it will fail on names starting with [a-f]. Such names will not be converted to an ip address, but be returned unchanged.

Issue Links

• relates to: HADOOP-6824 Improve NetUtils:normalizeHostName