Podman: how to resolve the hostname of a pod deployed using Kubernetes YAML

Question

I'm using podman 4.5-dev I have two pods deployed using: podman kube play foo.yaml podman kube play bar.yaml

I specified the pods' hostnames in the files, but they won't get resolved inside the containers. I verified that the pods are in the same network.

Is there some DNS configuration missing? Should I use a Services? The official docs lack of a precise indication about this topic

Here's one of the two pods's YAML (the other one has the same keys with different values):

apiVersion: v1
kind: Pod
metadata:
  labels:
    app: postgres
  name: postgres
spec:
  hostname: postgres
  containers:
  - name: pgadmin-container
    image: docker.io/dpage/pgadmin4:latest
    ports:
    - containerPort: 80
      hostPort: 9876

Here's some terminal output that could be useful:

[daniele@localhost]$ podman pod inspect xptssrv |grep -ni network
25:          "HostNetwork": false,
34:          "Networks": [
35:               "podman-default-kube-network"
37:          "NetworkOptions": null,


[daniele@localhost]$ podman pod inspect postgres |grep -ni network
25:          "HostNetwork": false,
34:          "Networks": [
35:               "podman-default-kube-network"
37:          "NetworkOptions": null,



[daniele@localhost]$ podman network inspect podman-default-kube-network |grep "" -n
1:[
2:     {
3:          "name": "podman-default-kube-network",
4:          "id": "a4dcf21f020ee4e36651c11256cbe884182552e835eaaafd409153cd21dca4cc",
5:          "driver": "bridge",
6:          "network_interface": "cni-podman1",
7:          "created": "2023-02-21T23:03:25.800256942+01:00",
8:          "subnets": [
9:               {
10:                    "subnet": "10.89.0.0/24",
11:                    "gateway": "10.89.0.1"
12:               }
13:          ],
14:          "ipv6_enabled": false,
15:          "internal": false,
16:          "dns_enabled": false,
17:          "ipam_options": {
18:               "driver": "host-local"
19:          }
20:     }
21:]

[daniele@localhost pods]$ podman exec  xptssrv-xptssrv-container cat /etc/resolv.conf 
nameserver 192.168.1.6
nameserver 8.8.8.8

Answer 1

Edit your network settings in /etc/containers/net.d/podman-default-kube-network.conflist Change this line

"dns_enabled": false,

To this:

"dns_enabled": true,

Then reboot and up your yaml and try to resolve this:

postgres_pgadmin-container_1

Or maybe this:

postgres_postgres_1

Edit1

Just copy the config file:

sudo cp /usr/share/containers/containers.conf /etc/containers/containers.conf

Then in the file change the network backend to netavark using the following command:

sed -i "/^\s*\#*\s*network_backend\s*=.*$/ s/^.*$/network_backend = \"netavark\"/" /etc/containers/containers.conf

Notice: I think it's better to restart you system in order to apply changes.