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Subject [1/3] accumulo git commit: ACCUMULO-4176: Add blurb to troubleshooting doc for tserver.walog.max.age
Date Mon, 09 May 2016 18:37:57 GMT
Repository: accumulo
Updated Branches:
  refs/heads/master 4e2adbb3d -> 7c812c3a2

ACCUMULO-4176: Add blurb to troubleshooting doc for tserver.walog.max.age


Branch: refs/heads/master
Commit: b95a1f951298d7497afdf9f0c5093ea17f3ad3be
Parents: a38c9ad
Author: Dave Marion <>
Authored: Mon May 9 13:51:57 2016 -0400
Committer: Dave Marion <>
Committed: Mon May 9 13:51:57 2016 -0400

 docs/src/main/asciidoc/chapters/troubleshooting.txt | 5 +++++
 1 file changed, 5 insertions(+)
diff --git a/docs/src/main/asciidoc/chapters/troubleshooting.txt b/docs/src/main/asciidoc/chapters/troubleshooting.txt
index 9546638..667303f 100644
--- a/docs/src/main/asciidoc/chapters/troubleshooting.txt
+++ b/docs/src/main/asciidoc/chapters/troubleshooting.txt
@@ -821,3 +821,8 @@ maximum file limit, so it began merging memory updates with files to keep
the fi
 slows down ingest performance, so knowing there are many files like this tells you that the
 is struggling to keep up with ingest vs the compaction strategy which reduces the number
of files.
+### HDFS Decommissioning Issues
+*Q*: My Hadoop DataNode is hung for hours trying to decommission.
+*A*: Write Ahead Logs stay open until they hit the size threshold, which could be many hours
or days in some cases. These open files will prevent a DN from finishing its decommissioning
process (HDFS-3599) in some versions of Hadoop 2. If you stop the DN, then the WALog file
will not be closed and you could lose data. To work around this issue, we now close WALogs
on a time period specified by the property +tserver.walog.max.age+ with a default period of
24 hours.

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