Provided by: syslog-ng-core_4.8.1-4_amd64 
NAME
loggen - Generate syslog messages at a specified rate
SYNOPSIS
loggen [options]target [port]
DESCRIPTION
NOTE: The loggen application is distributed with the syslog-ng system logging application, and is usually
part of the syslog-ng package. The latest version of the syslog-ng application is available at the
official syslog-ng website[1].
This manual page is only an abstract, for the complete documentation of syslog-ng, see The syslog-ng
Administrator Guide[2].
The loggen application is tool to test and stress-test your syslog server and the connection to the
server. It can send syslog messages to the server at a specified rate, using a number of connection types
and protocols, including TCP, UDP, and unix domain sockets. The messages can be generated automatically
(repeating the PADDstring over and over), or read from a file or the standard input.
When loggen finishes sending the messages, it displays the following statistics:
• average rate: Average rate the messages were sent in messages/second.
• count: The total number of messages sent.
• time: The time required to send the messages in seconds.
• average message size: The average size of the sent messages in bytes.
• bandwidth: The average bandwidth used for sending the messages in kilobytes/second.
OPTIONS
--active-connections <number-of-connections>
Number of connections loggen will use to send messages to the destination. This option is usable only
when using TCP or TLS connections to the destination. Default value: 1
The loggen utility waits until every connection is established before starting to send messages. See
also the --idle-connections option.
--csv or -C
Send the statistics of the sent messages to stdout as CSV. This can be used for plotting the message
rate.
--dgram or -D
Use datagram socket (UDP or unix-dgram) to send the messages to the target. Requires the --inet
option as well.
--dont-parse or -d
Do not parse the lines read from the input files, send them as received.
--help or -h
Display a brief help message.
--idle-connections <number-of-connections>
Number of idle connections loggen will establish to the destination. Note that loggen will not send
any messages on idle connections, but the connection is kept open using keep-alive messages. This
option is usable only when using TCP or TLS connections to the destination. See also the
--active-connections option. Default value: 0
--inet or -i
Use the TCP (by default) or UDP (when used together with the --dgram option) protocol to send the
messages to the target.
--interval <seconds> or -I <seconds>
The number of seconds loggen will run. Default value: 10
Note
Note that when the --interval and --number are used together, loggen will send messages until the
period set in --interval expires or the amount of messages set in --number is reached, whichever
happens first.
--ipv6 or -6
Specify the destination using its IPv6 address. Note that the destination must have a real IPv6
address.
--loop-reading or -l
Read the file specified in --read-file option in loop: loggen will start reading from the beginning
of the file when it reaches the end of the file.
--number <number-of-messages> or -n <number-of-messages>
Number of messages to generate.
Note
Note that when the --interval and --number are used together, loggen will send messages until the
period set in --interval expires or the amount of messages set in --number is reached, whichever
happens first.
--no-framing or -F
Do not use the framing of the IETF-syslog protocol style, even if the syslog-proto option is set.
--quiet or -Q
Output statistics only when the execution of loggen is finished. If not set, the statistics are
displayed every second.
--permanent or -T
Keep sending logs indefinitely, without time limit.
--rate <message/second> or -r <message/second>
The number of messages generated per second for every active connection. Default value: 1000
--read-file <filename> or -R <filename>
Read the messages from a file and send them to the target. See also the --skip-tokens option.
Specify - as the input file to read messages from the standard input (stdio). Note that when reading
messages from the standard input, loggen can only use a single thread. The -R - parameters must be
placed at end of command, like: loggen 127.0.0.1 1061 --read-file -
--sdata <data-to-send> or -p <data-to-send>
Send the argument of the --sdata option as the SDATA part of IETF-syslog (RFC5424 formatted)
messages. Use it together with the --syslog-proto option. For example: --sdata "[test name=\"value\"]
--size <message-size> or -s <message-size>
The size of a syslog message in bytes. Default value: 256. Minimum value: 127 bytes, maximum value:
8192 bytes.
--skip-tokens <number>
Skips the specified number of space-separated tokens (words) at the beginning of every line. For
example, if the messages in the file look like foo bar message, --skip-tokens 2 skips the foo bar
part of the line, and sends only the message part. Works only when used together with the --read-file
parameter. Default value: 0
--stream or -S
Use a stream socket (TCP or unix-stream) to send the messages to the target.
--syslog-proto or -P
Use the new IETF-syslog message format as specified in RFC5424. By default, loggen uses the legacy
BSD-syslog message format (as described in RFC3164). See also the --no-framing option.
--unix </path/to/socket> or -x </path/to/socket>
Use a UNIX domain socket to send the messages to the target.
--use-ssl or -U
Use an SSL-encrypted channel to send the messages to the target. Note that it is not possible to
check the certificate of the target, or to perform mutual authentication.
--version or -V
Display version number of syslog-ng.
EXAMPLES
The following command generates 100 messages per second for ten minutes, and sends them to port 2010 of
the localhost via TCP. Each message is 300 bytes long.
loggen --stream --size 300 --rate 100 --interval 600 127.0.0.1 2010
The following command is similar to the one above, but uses the UDP protocol.
loggen --inet --dgram --size 300 --rate 100 --interval 600 127.0.0.1 2010
Send a single message on TCP6 to the ::1 IPv6 address, port 1061:
loggen --ipv6 --number 1 ::1 1061
Send a single message on UDP6 to the ::1 IPv6 address, port 1061:
loggen --ipv6 --dgram --number 1 ::1 1061
Send a single message using a unix domain-socket:
loggen --unix --stream --number 1 </path/to/socket>
Read messages from the standard input (stdio) and send them to the localhost:
loggen 127.0.0.1 1061 --read-file -
FILES
/usr/bin/loggen
SEE ALSO
syslog-ng.conf(5)
Note
For the detailed documentation of see The 4.8 Administrator Guide[2]
If you experience any problems or need help with syslog-ng, visit the syslog-ng mailing list[3].
For news and notifications about of syslog-ng, visit the syslog-ng blogs[4].
AUTHOR
This manual page was written by the Balabit Documentation Team <documentation@balabit.com>.
COPYRIGHT
NOTES
1. the official syslog-ng website
https://www.balabit.com/log-management
2. The syslog-ng Administrator Guide
https://www.syslog-ng.com/technical-documents/doc/syslog-ng-open-source-edition/3.37/administration-guide
3. syslog-ng mailing list
https://lists.balabit.hu/mailman/listinfo/syslog-ng
4. syslog-ng blogs
https://syslog-ng.org/blogs/
4.8 03/16/2025 LOGGEN(1)