How to have a custom /etc/hosts in image?

[daledude]

Not sure if this is a bug or intended. I find conflicting information regarding this so please excuse if I didn't file enough information.

I have code in Dockerfile to create a custom /etc/hosts file. But, saving and extracting the built image from "podman build" shows the /etc/hosts file is empty. I want to create my own /etc/hosts and use "podman run --no-hosts" but the build process seems to zero out my /etc/hosts file.

The description for --no-hosts is:
Do not create /etc/hosts within the container, instead use the version from the image

But, if my /etc/hosts is emptied at build time how can I use the version from the image?

[Luap99]

I think you have to run with podman build --network disabled to use the actual /etc/hosts file from the image and not a bind mount from the host.

[daledude]

Hi @Luap99

disabled isn't an option. I tried podman build --network none but it still zero's my image /etc/hosts file at build time.

[ttys3]

1. solution 1: use global
   edit /etc/containers/containers.conf and change #dns_searches = [] to

dns_servers = ["custom-dns1", "custom-dns2"]

replace custom-dns* with your own DNS

2. solution 2: create the container with custom dns options.

see docs of podman create

[alitvak69]

@ttys3 This answer was unrelated to a actual question.
I found this link which states that changing hosts file can only happen in runtime for docker and since podman tries to be 100% docker compatible may be it is the case here.
PTL
https://stackoverflow.com/a/40721996

[rhatdan]

If you don't want the /etc/hosts file to be modified, you can use the --no-hosts option.

[Luap99]

This option does not exists for podman build

[rhatdan]

Ok, I guess we should add that.

[github-actions]

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