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jgngo
jgngo

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Podman Tips

If you are using WSL, you may want to install podman instead of docker. It is a drop-in replacement made by Red Hat. You won't need to do sudo service docker start before running docker commands. To install in WSL, just do the following.

sudo apt install podman
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Adding dockerhub registry in the default search

Update the configuration file so it can search the docker.io image registry.

/etc/containers/registries.conf

unqualified-search-registries = ['docker.io']
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Access localhost from the container

To allow a running container to access a service running on the host like a database server, a special hostname host.containers.internal is created in the container /etc/hosts that points to the local IP.

PostgreSQL by default only allows connections from localhost. You will need to configure it to allow remote connections. Update postgresql.conf and pg_hba.conf

postgresql.conf
listen_addresses = '*'

pg_hba.conf
host    all             all             0.0.0.0/0            scram-sha-256
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podman run --rm --net=slirp4netns:allow_host_loopback=true -it alpine /bin/sh
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The parameter --net allows access to the host. If you run podman as a regular user, the default network setting is slirp4netns with the allow_host_loopback set to false. This parameter needs to be set to true to allow slirp4netns to reach the host loopback IP host.containers.internal

https://docs.podman.io/en/latest/markdown/podman-run.1.html

For docker-compose or podman-compose, add the following under the service.

network_mode: slirp4netns:allow_host_loopback=true
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Set as default

If there is no existing configuration file in /etc/containers/, create a copy of the default containers.conf so you can edit.

sudo cp /usr/share/containers/containers.conf /etc/cont
ainers/
sudo vi /etc/containers/containers.conf
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Uncomment and edit the following entry.

# Default options to pass to the slirp4netns binary.
# For example "allow_host_loopback=true"
#
network_cmd_options = ["allow_host_loopback=true"]
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Top comments (1)

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lamri_abdellahramdane_15 profile image
Lamri Abdellah Ramdane •

This is a very helpful article for developers using Podman. It provides practical tips for a smoother workflow, especially when dealing with connectivity to host services. Servbay is an excellent tool for this, as it provides a complete, pre-configured local development environment, letting you skip these individual configurations and get straight to building your app.