[HADOOP-6746] hadoop-daemon.sh does not append to log files

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 2.2.0
• Labels: script
• Target Version/s: 2.3.0
• Release Note: Open log files with append (rather than creating new files) so file truncation works. This allows log rotation tools to operate correctly without restarting Hadoop processes.
• Assignee: Akira Ajisaka
• Reporter: Travis Crawford
• Created: 03/May/10 19:19
• Updated: 30/Jul/14 22:15
• Resolved: 30/Jul/14 22:15

Description

Looking in hadoop-daemon.sh we see the start command redirects logs to the log file by creating a new file. It does not append to the log.

nohup nice -n $HADOOP_NICENESS "$HADOOP_HOME"/bin/hadoop --config $HADOOP_CONF_DIR $command "$@" > "$log" 2>&1 < /dev/null &

I believe output should be appended to the log file so logrotate copytruncate works. Currently a large log file cannot be truncated without restarting the running service, which causes issues in production environments.

The improved line would be exactly the same, except use >> to open the log file in append mode.

nohup nice -n $HADOOP_NICENESS "$HADOOP_HOME"/bin/hadoop --config $HADOOP_CONF_DIR $command "$@" >> "$log" 2>&1 < /dev/null &

Issue Links

• is duplicated by: HADOOP-9902 Shell script rewrite