You'll need to disable imklog or rsyslogd won't start:
module(load="imklog") # provides kernel logging support
This is essential unless you give full privileges to your container.
Here is a full working rsyslog config in Ubuntu/Debian:
module(load="imuxsock") # provides support for local system logging
$ActionFileDefaultTemplate RSYSLOG_TraditionalFileFormat
$FileOwner root........
For many reasons you may be dealing with a standard text file and you want to know if there are any duplicate lines:
Here's how you do it:
cat filename|uniq -c
The "uniq -c" program counts how many time each line occurs.........