py3syslog

Python 3 implementation of a simple UDP syslog server which inserts the recieved messages into a MariaDB [1] or MySQL [2] database.

About

The Python script will start a syslog server which inserts the recieved messages into a MariaDB [1] or MySQL [2] database.

Every time the script is executed it will check if the database and table exist and if not create them. Then the script is executed until it will be manually closed. Every time a message is recieved on the defined port the data will be decoded as UTF-8, inserted in the database and printed out in the terminal.

Be aware that the UDP packages are not encypted. It is taken care off avoiding SQL injections because the server might be facing the internet.

The script uses the python module socketserver [3] and the external module mysql-connector-python [4] . See requirements.txt for installed packages and the used versions. The file is created with pip3 freeze > requirements.txt.

Usage

First install the required mysql-connector-python module in the global Python 3 environment or in a virtual Python 3 environment. The latter has the advantage that the packages are isolated from other projects and also from the system wide installed global once. If things get messed up, the virtual environment can just be deleted and created from scratch again. For more informations about virtual environments in Python 3, see venv1 [5] and venv2 [6] .

pip3 install mysql-connector-python

Then modify the PORT, db_name, table_name, db_user, db_password, db_host and db_port parameters in the syslogserver.py script and execute it.

python3 syslogserver.py

Or use e.g. tmux [7] to execute it in the background.

Systemd service

An example .service file is also included to show how to run the syslog server as a systemd service at startup. For more informations, see systemd.service [8] . In the example .service file a virtual Python 3 environment is used to execute the script. Also the script will be automatically restarted if it crashes to ensure that the syslog server is always running. The local user name and the path to the virtual Python 3 environment needs to be adjusted before it can be used.

To activate the systemd service execute the following commands.

sudo cp syslogserver.service /etc/systemd/system/

sudo systemctl daemon-reload

sudo systemctl start syslogserver.service

sudo systemctl enable syslogserver.service

Example Mikrotik RouterOS

The script was developed to recieve syslog messages from a MikroTik [9] wAP LTE kit [10] and insert them into a MariaDB [1] database to be able to display them via Grafana [12] .

RouterOS

The following settings are used in RouterOS. They need to be applied via CLI [11] . Change remote and remote-port to the one where the syslog server is listening.

/system logging action>
set 3 remote=123.123.123.123 remote-port=12312

Next command just prints out the settings of /system logging action .

/system logging action> print
Flags: * - default
0 * name="memory" target=memory memory-lines=1000 memory-stop-on-full=no

1 * name="disk" target=disk disk-file-name="flash/log"
    disk-lines-per-file=1000 disk-file-count=2 disk-stop-on-full=no

2 * name="echo" target=echo remember=yes

3 * name="remote" target=remote remote=123.123.123.123 remote-port=12312
    src-address=0.0.0.0 bsd-syslog=no syslog-time-format=bsd-syslog
    syslog-facility=daemon syslog-severity=auto

It is also needed to add the remote syslog server as a destination for logs on the wanted topics. The prefix= option is optional but useful to distinguish between different devices as it is added in the logs which are sent to the remote syslog server.

/system logging>
add action=remote prefix=example_prefix topics=info
add action=remote prefix=example_prefix topics=error
add action=remote prefix=example_prefix topics=warning
add action=remote prefix=example_prefix topics=critical

Grafana

Grafana [12] is used to display the syslog messages. In Grafana [12] the database has to be added as a datasource [13] . Then a table [14] with following SQL query in the Metrics tab can be added to a dashboard. The SQL query has to be adjusted to the used database/table/columns structure, see script syslogserver.py for more details how the database/table/columns are created. The AND message LIKE '%example_prefix%' part of the SQL query is used to display only a certain device based on the above used prefix= option.

SELECT
inserted_utc,
message
FROM logging.logs
WHERE $__timeFilter(inserted_utc) AND message LIKE '%example_prefix%'
ORDER BY inserted_utc DESC

Credits

https://gist.github.com/marcelom/4218010

References

[1]	(1, 2, 3) https://mariadb.org/

[2]	(1, 2) https://www.mysql.com/

[3]	https://docs.python.org/3/library/socketserver.html

[4]	https://pypi.org/project/mysql-connector-python/

[5]	https://docs.python.org/3/tutorial/venv.html

[6]	https://docs.python.org/3/library/venv.html

[7]	https://en.wikipedia.org/wiki/Tmux

[8]	https://www.raspberrypi.org/documentation/linux/usage/systemd.md

[9]	https://mikrotik.com/

[10]	https://mikrotik.com/product/wap_lte_kit

[11]	https://wiki.mikrotik.com/wiki/Manual:First_time_startup#CLI

[12]	(1, 2, 3) https://grafana.com/

[13]	http://docs.grafana.org/features/datasources/mysql/

[14]	http://docs.grafana.org/features/panels/table_panel/