Skip to content

No Events In LogZilla

If LogZilla is showing no events from other systems there are several ways to determine the cause.

Check the log

Check LogZilla's internal log file using:

sudo tail -f /var/log/logzilla/logzilla.log

Verify that the source is sending

tcpdump can be used on the LogZilla server to determine if the remote host's events are reaching the LogZilla server:

If your source device/app is not sending to udp port 514, then change the line below to accommodate:

sudo tcpdump -vvv -i $(awk '$2 == 00000000 { print $1 }' /proc/net/route) udp port 514

This will listen on the Ethernet interface assigned to the default gateway for incoming events on udp port 514 (the default for UDP syslog events).

Note that if the LogZilla server's appropriate Ethernet interface or the configured listening port is different than shown, those parameters to tcpdump above should be changed accordingly.

For example:

  • -i (used below) manually specifies the interface to use instead of the default gateway in the example above
sudo tcpdump -vvv -i p1p1 udp port 514

After running the command, you will see data similar to:

tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
    17:01:01.955523 IP (tos 0x0, ttl 64, id 44193, offset 0, flags [DF], proto UDP (17), length 272) > [udp sum ok] SYSLOG, length: 244
        Facility kernel (0), Severity warning (4)
        Msg: Sep  3 13:01:02 www kernel: [UFW BLOCK] IN=eth0 OUT= MAC=01:22:33:02:e5:01:44:c5:9c:f9:18:30:08:00 SRC= DST= LEN=60 TOS=0x00 PREC=0x00 TTL=44 ID=65267 DF PROTO=TCP SPT=41410 DPT=22 WINDOW=14600 RES=0x00 SYN URGP=0 \0x0a
        0x0000:  3c34 3e53 6570 2

Set LogZilla's syslog container to Debug Mode

Once you have verified that events are being received as noted above, try enabling debug mode on the lz_syslog container by issuing the following command from the shell prompt:

sudo docker exec -it lz_syslog bash -c 'syslog-ng-ctl debug --set=on'
sudo docker logs lz_syslog --tail 100 -f

WARNING: Debug mode should be disabled once you are finished checking the output:

sudo docker exec -it lz_syslog bash -c 'syslog-ng-ctl debug --set=off'

If this indicates that events are being received but are still not appearing in LogZilla, the next step is to verify that the syslog container is processing them properly.

Log to a debug file

Enable syslog debug to file using:

sudo logzilla config syslog_debug 1

Once troubleshooting is complete, debug logging should be disabled, since it generates extra load on the syslog process and can quickly fill up disk: logzilla config syslog_debug 0.

All raw log events will be logged to /var/log/logzilla/syslog/debug.log

WARNING: Leaving raw debug log enabled can fill your disk. Be sure to disable it once you are finished troubleshooting.

View the logs using:

sudo tail -F /var/log/logzilla/syslog/debug.log

This should indicate entries coming in. If not, a sample log can be generated locally by:

sudo logger -T -P 514 --rfc3164 -n localhost -p local0.emerg -t "test" "rfc3164 event test on TCP Port 514 from $(hostname)"
sudo logger -u -P 514 --rfc3164 -n localhost -p local0.emerg -t "test" "rfc3164 event test on UDP Port 514 from $(hostname)"

Any errors displayed should help narrow down any communication issues.

For more diagnostics, there is also another log file generated when syslog debugging is on. This file is located in /var/log/logzilla/syslog/debug-json.log It contains a JSON document for each line with details of the events received and initially processed by syslog.

The JSON-based log can be enabled using:

sudo logzilla config syslog_debug_json 1

Once troubleshooting is complete, debug logging should be disabled, since it generates extra load on the syslog process and can quickly fill up disk: logzilla config syslog_debug_json 0.

Raw Tcpdump Capture

If LogZilla is still showing no received events, support is available at Please include the output from the following command:

  1. Ensure that the host sending events is sending to LogZilla on udp port 514. Otherwise, our support team has no way to replay your environment in the lab.
  2. Run the command below to capture a sample of your incoming event stream.

    Note: Change -G 1200 below to a larger number if your LogZilla server doesn't normally receive a large amount of events. Ideally, you want to capture a large enough window to ensure that the event(s) in question can be captured.

    # "1200" below equates to 20 Minutes
    # "86400" would be 24 hours
    # In some cases, support may ask that you capture an entire days' worth in order to have a proper sample of event data
    tcpdump -i $(awk '$2 == 00000000 { print $1 }' /proc/net/route) udp port 514 -nnvvXSs 0 -G 1200 -W 1 -z gzip -w /tmp/$(hostname).pcap
  3. After 20 Minutes (or the time specified above in the -G 1200 portion, the capture will automatically stop and place a .gz file in /tmp/ with the hostname as the filename. For example /tmp/myhost.pcap.gz

In your support ticket please include the installed LogZilla version, which is found at the bottom right corner of the LogZilla Web Interface, or by typing sudo logzilla version from the console.