Jing Zhao created HDFS-5080:
-------------------------------
Summary: BootstrapStandby not working with QJM when the existing
NN is active
Key: HDFS-5080
URL: https://issues.apache.org/jira/browse/HDFS-5080
Project: Hadoop HDFS
Issue Type: Bug
Affects Versions: 3.0.0
Reporter: Jing Zhao
Assignee: Jing Zhao
Currently when QJM is used, running BootstrapStandby while the existing NN is
active can get the following exception:
{code}
FATAL ha.BootstrapStandby: Unable to read transaction ids 6175397-6175405 from
the configured shared edits storage. Please copy these logs into the shared
edits storage or call saveNamespace on the active node.
Error: Gap in transactions. Expected to be able to read up until at least txid
6175405 but unable to find any edit logs containing txid 6175405
java.io.IOException: Gap in transactions. Expected to be able to read up until
at least txid 6175405 but unable to find any edit logs containing txid 6175405
at
org.apache.hadoop.hdfs.server.namenode.FSEditLog.checkForGaps(FSEditLog.java:1300)
at
org.apache.hadoop.hdfs.server.namenode.FSEditLog.selectInputStreams(FSEditLog.java:1258)
at
org.apache.hadoop.hdfs.server.namenode.ha.BootstrapStandby.checkLogsAvailableForRead(BootstrapStandby.java:229)
{code}
Looks like the cause of the exception is that, when the active NN is queries by
BootstrapStandby about the last written transaction ID, the in-progress edit
log segment is included. However, when journal nodes are asked about the last
written transaction ID, in-progress edit log is excluded. This causes
BootstrapStandby#checkLogsAvailableForRead to complain gaps.
To fix this, we can either let journal nodes take into account the in-progress
editlog, or let active NN exclude the in-progress edit log segment.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
