红帽全球峰会12.4. Advantages of using Quadlets over the podman generate systemd command
You can use the Quadlets tool, which describes how to run a container in a format similar to regular systemd unit files.
Quadlet is available beginning with Podman v4.6.
Quadlets have many advantages over generating unit files by using the podman generate systemd command, such as:
-
Easy to maintain: The container descriptions focus on the relevant container details and hide technical details of running containers under
systemd. -
Automatically updated: Quadlets do not require manually regenerating unit files after an update. If a newer version of Podman is released, your service is automatically updated when the
systemclt daemon-reloadcommand is executed, for example, at boot time. - Simplified workflow: Thanks to the simplified syntax, you can create Quadlet files from scratch and deploy them anywhere.
- Support standard systemd options: Quadlet extends the existing systemd-unit syntax with new tables, for example, a table to configure a container.
Quadlet supports a subset of Kubernetes YAML capabilities. For more information, see the support matrix of supported YAML fields. You can generate the YAML files by using one of the following tools:
-
Podman:
podman generate kubecommand -
OpenShift:
oc generatecommand with the--dry-runoption -
Kubernetes:
kubectl createcommand with the--dry-runoption
Quadlet supports these unit file types:
Container units: Used to manage containers by running the
podman runcommand.-
File extension:
.container -
Section name:
[Container] -
Required fields:
Imagedescribing the container image the service runs
-
File extension:
Kube units: Used to manage containers defined in Kubernetes YAML files by running the
podman kube playcommand.-
File extension:
.kube -
Section name:
[Kube] -
Required fields:
Yamldefining the path to the Kubernetes YAML file
-
File extension:
Network units: Used to create Podman networks that may be referenced in
.containeror.kubefiles.-
File extension:
.network -
Section name:
[Network] - Required fields: None
-
File extension:
Volume units: Used to create Podman volumes that may be referenced in
.containerfiles.-
File extension:
.volume -
Section name:
[Volume] - Required fields: None
-
File extension:
For more information, see the podman-systemd.unit(5) man page on your system.
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