CentOS 8.x working with podman pods

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Home > CentOS > CentOS 8.x > Virtualization > podman > Working with podman pods

Create pod

Create a new pod with desired name

   podman pod create --name pod1


List pods

List pods of current system

   podman pod list


List all containers including containers which are member of pods

  • To list containers including containers of various pods use:
     podman ps --all

Note that all pods start with a default container named infra

  • To list containers including pod ID use:
     podman ps --all --pod


Run container inside pod

To run container inside pod use:

     podman run -dt --pod pod1 centos top


Create a pod and container inside pod with port publish string

To create a pod with exposed port use:

   sudo podman pod create -p 8080:80 --name web1
   sudo podman run -dt --pod web1 -p 8080 nginx:latest

Note that we need to publish all required ports during pod creation. The list cannot be changed later.


Remove pod with all its containers

To remove pod with all its containers (Stop containers, Remove containers and then remove pod) use:

   podman pod rm -f <pod-id>

Refer:


Communication between two containers within same pod

All containers with same pod share same network namespace. Hence communication between two containers can be done via 127.0.0.1 IP or localhost itself.

   podman pod create --name pod1
   podman run --pod pod1 --name pod1_httpd -dt httpd
   
   #Validate container belonging to pod is not member of host bridge
   podman inspect pod1_httpd | grep -i ip

   podman run --pod pod1 --name pod1_bash -it centos

   #Within container bash do following
   curl http://127.0.0.1/
   #<html><body><h1>It works!</h1></body></html>

   curl http://localhost/
   #<html><body><h1>It works!</h1></body></html>

   cat /etc/hosts
   #127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
   #::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
   #10.88.0.20	pod1

Here we can communicate with containers within pod and base host via infra container having IP 10.88.0.20 as listed in /etc/hosts IP. We can also see the IP by inspecting the pods infra container using commands such as:

   podman pod list
   podman inspect 6aac71d95792-infra | grep -i ip

where 6aac71d95792 should be replaced with pod ID (not infra ID) of the pod


Home > CentOS > CentOS 8.x > Virtualization > podman > Working with podman pods