Editing Systemd Units

Muppy provides complete editing features for Systemd Service Units.

Muppy uses these features to manage most of the services it installs (Traefik, Code Server, pglookout, Odoo, ...).

Muppy supports 2 workflows on Unit files:

• Workflow for creating a Unit file from a Muppy Template file
• Workflow for modifying an existing Unit file

Creation Workflow

This is the workflow Muppy uses to manage the services it installs. It is made up of the following steps:

• Create a Systemd Units by providing the Host and Unit Name.
• In the Configuration tab:
  • In the Unit file Template group, select the Systemd Default Unit File - Muppy template or a derivative.
  • Click the button
  • Enter the parameters of the systemd options group
  • Click the button so that Muppy generates the content of the Unit File.
• In the Unit File tab,
  • Click the button so that Muppy uploads the content of the Unit File to the location defined by Unit File Path.
  • Click the button if you want the service to start when the Host boots.
• Use the 4 buttons to control the Systemd Unit.

Modification Workflow

The objective - in the long run - of this workflow is to allow an existing Unit File to be managed through the Muppy interface by following these steps:

• Import a System Unit with the Wizard as described in Import Systemd Units Wizard
• Open the Service Unit in edit mode
• In the Unit File tab,
  • Click the button; Muppy will download the Unit File from the location defined by Unit File Path and display its content in Unit File Content.
  • Modify the content of the Unit File Content field
  • Click the button so that Muppy uploads the content of the Unit File to the location defined by Unit File Path.
  • Click the button so that the system takes the changes into account

Info

You can also generate the content of the Unit File using the variables of the configuration group and a specific Template file, as described in the previous paragraph.

Removing a Systemd Unit

Three buttons remove a unit. They differ in what they do on the Host.

Button	Where	What it does
Forget Unit	the header of the unit's form, and each line of the units list	Deletes the unit's record in Muppy, with the records of its aliases. The unit, its unit file and its state stay on the Host. A scan of the Host can import the unit again. From the form, you land on the Host.
Remove	each line of the units list	Stops and disables the unit on the Host, deletes its unit file, then deletes its record in Muppy.
Delete Unit File	the Unit File tab of the form, once the unit is disabled	Deletes the unit file on the Host. The record stays in Muppy.

Danger

Remove and Delete Unit File delete the file that Unit File Path names, wherever it lives. For a unit installed by a package (redis-server, cron, … under /usr/lib/systemd/system), that file belongs to the package: deleting it breaks the package. To stop monitoring such a unit, use Forget Unit.

Delete Unit File refuses a Unit File Path that is not absolute, or that ends with /: it deletes one file, never a directory.