[HDFS-3934] duplicative dfs_hosts entries handled wrong

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.0.1-alpha
• Fix Version/s: 2.1.0-beta
• Assignee: Colin McCabe
• Reporter: Andy Isaacson
• Created: 13/Sep/12 17:36
• Updated: 03/Sep/14 23:02
• Resolved: 14/Jun/13 20:26

Description

A dead DN listed in dfs_hosts_allow.txt by IP and in dfs_hosts_exclude.txt by hostname ends up being displayed twice in dfsnodelist.jsp?whatNodes=DEAD after the NN restarts because getDatanodeListForReport does not handle such a "pseudo-duplicate" correctly:

1. the "Remove any nodes we know about from the map" loop no longer has the knowledge to remove the spurious entries
2. the "The remaining nodes are ones that are referenced by the hosts files" loop does not do hostname lookups, so does not know that the IP and hostname refer to the same host.

Relatedly, such an IP-based dfs_hosts entry results in a cosmetic problem in the JSP output: The Node column shows ":50010" as the nodename, with HTML markup <a href="http://:50075/browseDirectory.jsp?namenodeInfoPort=50070&dir=%2F&nnaddr=172.29.97.196:8020" title="172.29.97.216:50010">:50010</a>.

Issue Links

• breaks: HDFS-6180 dead node count / listing is very broken in JMX and old GUI
• is related to: HDFS-4344 dfshealth.jsp throws NumberFormatException when dfs.hosts/dfs.hosts.exclude includes port number
• is related to: HDFS-4870 periodically re-resolve hostnames in included and excluded datanodes list