[HDFS-4957] NameNode failover should not fail because a DNS entry for a quorum node cannot be resolved

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 2.3.0, 2.6.0
• Component/s: qjm
• Assignee: John Zhuge
• Reporter: Colin McCabe
• Created: 03/Jul/13 22:46
• Updated: 25/Jul/22 11:24

Description

When a StandbyNameNode is becoming active, we should not bail out because a DNS entry for a quorum node cannot be resolved. Currently it does fail in this scenario, with a message like this:

2013-07-03 21:28:40,576 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Starting services required for active state
2013-07-03 21:28:40,579 FATAL org.apache.hadoop.hdfs.server.namenode.NameNode: Error encountered requiring NN shutdown. Shutting down immediately.
java.lang.IllegalArgumentException: Unable to construct journal, qjournal://hadoop-mm:8485;hadoop-nn-0:8485;hadoop-nn-1:8485/hadoop
at org.apache.hadoop.hdfs.server.namenode.FSEditLog.createJournal(FSEditLog.java:1254)
at org.apache.hadoop.hdfs.server.namenode.FSEditLog.initJournals(FSEditLog.java:226)
at org.apache.hadoop.hdfs.server.namenode.FSEditLog.initJournalsForWrite(FSEditLog.java:193)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startActiveServices(FSNamesystem.java:722)
<etc>

reported by Matt Bookman

Issue Links

• is related to: HDFS-8298 HA: NameNode should not shut down completely without quorum, doesn't recover from temporary network outages
• relates to: HDFS-4210 Throw helpful exception when DNS entry for JournalNode cannot be resolved