This guide will create a daemon service which runs diem-node and restarts on failure and on reboot.

Note that this guide:

• targets Ubuntu 20.4.
• assumes you have set up your environment correctly (see util/setup.sh).
• does not provision the tower service which is a separate concern from diem-node.

Background

systemd, is a linux utility for managing long-running services on linux. The validation service (diem-node) is one such long running service. The tower is another, but that is out of scope for this doc.

There are a few file paths you will be working from:

• ~/.0L/ will contain the node configurations
• ~/<project root>/diem-node: contains the source code
• ~/<project root>/target/release: will contain binaries produced by cargo

Quick Start

This will use a make recipe to start the node daemon and install the daemon configs.

A template ol/util/diem-node.service will be copied into your ~/.config/systemd/user/ path to setup the service. This is non-root template file which uses the home directory of the managing user of the service.

BEFORE PROCEEDING: Check that you have ol/util/diem-node.service in place.

Now the Makefile can do a number of things including coping that file to the usual place, and then (re)starting the service.

From the project root:

make daemon

Configure manually

Build binaries and copy to appropriate path

Use make bins install or alternatively:

Create the service configurations for Systemd

In ~/.config/systemd/user/ you should create a file like this. (Note: again, make daemon does this for you)

# this assumes that the managing user of the service is `node`, hence the `/home/node` home path prefix
[Unit]
Description=0L Node Service

[Service]
LimitNOFILE=20000
WorkingDirectory=/home/node/.0L
ExecStart=/home/node/bin/diem-node --config /home/node/.0L/validator.node.yaml

Restart=always
RestartSec=10s

# Make sure you CREATE the directory and file for your node.log
StandardOutput=file:/home/node/logs/node.log
StandardError=file:/home/node/logs/node.log

[Install]
WantedBy=multi-user.target
Alias=diem-node.service

NOTE: When you update any *service file, you must reload ststemctl

systemctl daemon-reload

Shortcuts

Watch diem-node logs

You can follow the logs by simply tailing the logs file.

tail -f ~/logs/node.log

Start the new service

make daemon or manually:

systemctl start diem-node.service

Stop the new service

make stop or manually:

systemctl stop diem-node.service

Enable the new service to start on boot

systemctl enable diem-node.service

Check status of the new service

systemctl status diem-node.service

if you have been successful when you run you will see:

● diem-node.service - OL Node Service
   Loaded: loaded (/lib/systemd/system/diem-node.service; enabled; vendor preset: enabled)
   Active: active (running) since Tue 2020-06-23 16:06:38 UTC; 10min ago
 Main PID: 15499 (diem-node)
    Tasks: 1 (limit: 4915)
   CGroup: /system.slice/diem-node.service
           └─15499 /usr/local/bin/diem-node --config /root/.0L/node.yaml

Set up proper logging

Logs are being written to a flat file. This is not ideal. You may want to configure journalctl.

https://www.digitalocean.com/community/tutorials/how-to-use-journalctl-to-view-and-manipulate-systemd-logs

Trouble shooting

Validator Wizard

If your config files have not been created you'll need to do onboarding. Check if you have a ~/.0L/0L.toml file. This is a sign that you are not yet onboarded.