daemonlogger(1) simple network logger and soft tap daemon


daemonlogger [Options]


daemonlogger is a simple network packet logger and soft tap daemon. It is able to log packets to file or mirror to another interface.



Show summary of options.


Show version of program.

-c <count>

Log <count> packets and exit.


Run as a daemon.

-f <bpf file>

Load bpf filter from file.


Flush the pcap buffer for each packet.

-g <group id>

Set group to <group id>.

-u <user name>

Set user to <user name>.

-i <interface>

Set interface to grab data from to <interface>.

-l <path>

Set log directory to <path>.

-m <count>

Generate <count> number of log files and exit.

-n <name>

Set ouput file prefix to <name>.

-o <interface>

Disable logging, instead mirror traffic from -i <interface> to -o <interface>.

-p <pidfile>

Set PID filename to <pidfile>.

-P <path>

Set PID path to <path>.


Activate ringbuffer mode.

-R <pcap file>

Read packets from <pcap file>

-s <bytes>

Automatically roll over the log file after <bytes>.

-S <snaplen>

Set number of bytes per packet to capture to <snaplen>.

-t <seconds>

Rollover the log file on time intervals. Append an 'm' to rollover on minute boundaries, 'h' to rollover on hour boundaries and 'd' to rollover on day boundaries. If no interval selector is used then the default rollover interval is in seconds. For example, "-t 60" rolls the log file over every 60 seconds and "-t 2h" rolls the log file over every two hours at the top of the hour. In the case of minute/hour/day-based rollovers, the will round to the next highest hour. For example, if the program is told to rollover every 2 hours and is started 38 minutes into the current hour it will add 2 to the current hour and rollover as scheduled at the top of the hour at <current hour> + 2. If the program was started at 13:38 it would roll over the logfile at 15:00.

-T <chroot dir>

Chroot daemonlogger to <chroot dir>


Select log file pruning behavior. Omitting this switch results in the default mode being used where the oldest log file in the logging directory is pruned. Setting the -z switch changes the behavior so that Daemonlogger will prune the oldest file from its current instantiation and leave files from older runs in the same logging directory alone


The daemonlogger README can be found at /usr/share/doc/daemonlogger/README.gz
The daemonlogger homepage can be found at <http://www.snort.org/users/roesch/Site/Daemonlogger/Daemonlogger.html>


daemonlogger was written by Martin Roesch <[email protected]>.

This manual page was written by Chris Taylor <[email protected]>, for the Debian project (but may be used by others).