Add dns config #1875
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Add dns config #1875
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joaoantoniocardoso
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This is a workaround to make the container's `resolv.conf` synchronized with the host's `resolv.conf`. To do that, we disallow docker from managing the container's DNS nameservers by unmounting the container's `/etc/resolv.conf`, and soft linking it to the binded host's `/etc/resolv.conf`. So for this to work, the container's `/etc/resolv.conf.host` file should be binded (read-only) to the host's `/etc/resolv.conf`, for our system, it's configured in `bootstrap/startup.json.default`, and a patch is added in `core/tools/blueos_startup_update` so systems with older bootstrap versions can also work with it. One detail is that because docker uses `mount` to bind the host's file to the container's file, if the file-descriptor of the file changes, the bind will be lost. To prevent this, the file being binded must be a hard link to the actual `/etc/resolv.conf`, and that hard link file is the one being binded. This hard link is being done in `core/tools/blueos_startup_update` as `/etc/resolv.conf.host`. To briefly understand why it is necessary, when the docker starts a container, it generates the container `/etc/resolv.conf` based on the host's one, or some docker configuration, however, during the container's lifetime, if the host's DNS configuration changes, the container's DNS doesn't follow it, making the container (possibly) unable to resolve DNSs correctly, failing the BlueOS Helper's internet connection check. By syncing the container's resolv.conf with the host's one, we make sure the container's DNS configuration follows the host's changes, thus, ensuring the container is able to resolve DNSs correctly.
… tabbed container with both Interface Priority and Dns Configuraiton
…ly button when loading
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joaoantoniocardoso
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| def file_exists(file_name: str) -> bool: | ||
| command = f'sudo test -e "{file_name}"' | ||
| output = run_command(command, True) | ||
| print(output) |
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is these prints for debug ?
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yes, they allow us to inspect what happened on the Linux side
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Closes #1871
Demonstration:
dns_menu_demonstration.mp4