notifications on system startup, shutdown and service failure

Systemd services to announce system startup and shutdown via ntfy.sh notifications.

Install

To install, copy the service files into /etc/systemd/system/.

Optionally, copy ntfy-failure@.service and test-fail.service into /etc/systemd/user/ to allow them to be used for user services.
In this case, for ntfy-failure use the ExecStart with the --user flag added to the journalctl command. Otherwise, it defaults to the system logs, which the current user might not have access to and which likely won't contain the relevant error message.

Usage

Create a topic on ntfy.sh (for a custom instance, see customization below) and enable the services using yourTopicName:

systemctl enable ntfy-startup@yourTopicName.service
systemctl enable ntfy-shutdown@yourTopicName.service

To just test if it works, use start instead of enable.

For the ntfy-failure@.service an override is required to set the topic: systemctl [--user] edit ntfy-failure@.service and add:

[Service]
Environment=NTFY_TOPIC=yourTopicName

To test if this works run systemctl [--user] start test-fail.

Now, you can set OnFailure=ntfy-failure@$i.service in the [Unit] section of any service or unit you want. Even globally for all services in /etc/systemd/system/service.d/onfailure.conf and/or in /etc/systemd/user/service.d/onfailure.conf:

[Unit]
OnFailure=ntfy-failure@%i.service

Customization

Aside from directly editing the service files, they can be customized using override configurations (conf file in /etc/systemd/system/ntfy-startup@yourTopicName.service.d/ or using systemctl edit ntfy-startup@yourTopicName.service).

The following environment variables are intended to be customizable:

Variable name	Description	Default value	supported by startup	supported by shutdown	supported by failure
NTFY_URL	Base URL to self hosted instance.	https://ntfy.sh	✅️	✅️	✅
NTFY_TAGS	Tags/Emoji displayed with the message, see https://docs.ntfy.sh/emojis/	green_circle 🟢️ or red_circle 🔴️ or warning ⚠️	✅️	✅️	✅
NTFY_MESSAGE	Additional message content (after "hostname is online")	Startup time: $(uptime)	✅️	❌️	❌
NTFY_TOPIC	Specify topic to publish to. Only for ntfy-failure - set this as part of the service name for startup/shutown instead.		❌	❌	✅

E.g., a message to display the public IPv4, IPv6 and local IP:

[Service]
Environment=NTFY_MESSAGE="IPv4: $(dig @resolver3.opendns.com myip.opendns.com +short -4) - IPv6: $(dig @resolver3.opendns.com myip.opendns.com +short -6) - Local IPs: $(hostname -i)"