(2016-11-07)
Problem
CentOS 6 uses rsyslog 5.8.xxx which has rate limiting enabled. When too much comes in too fast, rsyslog says something like:
imuxsock begins to drop messages from pid $PID due to rate-limiting
Solution
Add to /etc/rsyslog.conf:
$SystemLogRateLimitInterval 0
$SystemLogRateLimitBurst 0
Note that this won't do anything to deal with losses that are udp-getting-dropped problems, but it raises the threshold of trouble somewhat higher than it otherwise would be.
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