Podman 5.3 changes for improved networking experience with pasta
Blogs, articles, and tips from the Podman development team on Podman, Buildah, Skopeo, and a host of other related container projects.
As of Podman 5.0 we default to “pasta” as a rootless networking application to provide network connectivity for rootless containers. Compared to our previous default, slirp4netns, pasta works a bit differently. For instance, pasta, by default, does not use Network Address Translation (NAT). This means it will copy the host address into the container as well, which means both the host and container namespace use the same IP address. This, in turn, means if you try to connect to the host IP from the container, it will refer to itself, not the host. Many users were confused by the lack of connectivity between the host and the container in this situation.
Also, for quite some time, podman has provided the host.containers.internal host entry in containers to allow containers to reach the host. Podman tried to be smart enough to not add the same host IP that is already used in the container namespace to avoid the issue. However, in many cases, the host only has one IP address (excluding localhost), so in this case Podman was unable to provide a suitable IP address for host.containers.internal; thus, the entry was not added.
