systemd: Failed to start {service}

systemd: Failed to start {service}

systemd produces the "Failed to start" message when a service unit cannot complete its startup sequence.

When systemd Produces This Error

systemd reports "Failed to start" when the ExecStart command returns a non-zero exit code, when the binary specified in ExecStart does not exist, or when the unit file contains syntax errors. The error appears in systemctl status output and in the systemd journal.

What Causes "Failed to start" in systemd

systemd fails to start a service when the binary path in ExecStart is incorrect or the file lacks execute permissions. The kernel returns ENOENT (file not found) or EACCES (permission denied), which systemd surfaces as exit status 203 (EXEC) or 217 (USER).

systemd also fails to start a service when a Requires= or BindsTo= dependency fails. If the required unit cannot start, systemd cancels the dependent service and reports the failure.

A misconfigured User= or Group= directive causes systemd to fail with exit status 217. This happens when the specified user or group does not exist on the system.

How to Fix "Failed to start" in systemd

1. Check the service status for the exit code:

   sudo systemctl status myapp.service

2. Read the journal for detailed error messages:

   sudo journalctl -u myapp.service -n 30 --no-pager

3. Verify the ExecStart binary exists and is executable:

   ls -la /path/to/binary

4. Verify the User= and Group= exist:

   id myapp

5. Validate the unit file syntax:

   sudo systemd-analyze verify /etc/systemd/system/myapp.service

6. After fixing the issue, reload and restart:

   sudo systemctl daemon-reload
   sudo systemctl restart myapp.service

How to Verify the Fix

systemctl status should show Active: active (running) with no error codes.