Viewing Nebula logs

This guide explains how to view logs for Nebula in each of the supported platforms. Please note that these instructions are approximations as there are many ways that Nebula can be installed.

Changing the log level

The level of detail is set by logging.level. To turn up logging on a running Nebula without editing its config, use nebula ctl on the host:

sudo nebula ctl log-level debug
# and back again when you are done
sudo nebula ctl log-level info

nebula ctl log-format json switches the format the same way. A config reload sets both back to the configured values.

Linux

Logs

journalctl --unit=nebula --follow

Service status

systemctl status nebula

# outputs
● nebula.service - Nebula overlay networking tool
     Loaded: loaded (/etc/systemd/system/nebula.service; enabled; vendor preset: enabled)
     Active: active (running) since Wed 2022-11-30 16:07:48 CST; 2min 3s ago
   Main PID: 546 (nebula)
      Tasks: 10 (limit: 4560)
     Memory: 19.2M
     CGroup: /system.slice/nebula.service
             └─546 /usr/local/bin/nebula -config /etc/nebula/config.yml

# ... shows nebula logs ...

macOS

Logs

sudo tail -f /opt/homebrew/var/log/nebula.*

Another useful tool for viewing logs is the built-in Console.app. To access the logs, select File -> Open from the menu and then press Cmd + Shift + G in the file picker, which will allow you to enter /opt/homebrew/var/log/nebula.log into the textbox.

Service status

launchctl list homebrew.mxcl.nebula

{
  "StandardOutPath" = "/opt/homebrew/var/log/nebula.log";
  "LimitLoadToSessionType" = "Aqua";
  "StandardErrorPath" = "/opt/homebrew/var/log/nebula.log";
  "Label" = "homebrew.mxcl.nebula";
  "OnDemand" = false;
  "LastExitStatus" = 256;
  "Program" = "/opt/homebrew/opt/nebula/bin/nebula";
  "ProgramArguments" = (
    "/opt/homebrew/opt/nebula/bin/nebula";
    "-config";
    "/opt/homebrew/etc/nebula/config.yml";
  );
};

Windows

Logs

Open the Event Viewer app, click on Custom Views -> Administrative Events -> manually enter nebula for "Event sources".

You can also make a "Custom View" which filters on the nebula source.

Custom events viewer form showing all logs selected

Custom events viewer form showing nebula entered within the Source field

Service status

To check the status of the service, open Services app, and find the Defined Networking Client service in the list. You should be able to see the status and start or stop the service.

Services app showing the status of the nebula service

Android / iOS

Logs

Tap on the site in question and tap "View Logs" on the details page for that site. You can then read, share, or delete your logs.