Add network interface binding documentation

[mohsenrezaeithe]

Fixes #1006

This would help users of the Docker container approach to be able to bind their updater to a specific network interface and get the right public IP.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.94%. Comparing base (58dd607) to head (8d73a02).
Report is 1 commits behind head on main.

Additional details and impacted files

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  Coverage   94.94%   94.94%           
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  Files          62       62           
  Lines        3366     3366           
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  Hits         3196     3196           
  Misses        158      158           
  Partials       12       12           

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[favonia]

Thank you. I have two broad suggestions:

1. I prefer not to clutter the initial template, especially when the setting network_mode: might conflict with networks:.
2. Perhaps we should warn that this might bypass quotas or firewalls for a specific network interface. For instance, the specially routed traffic might not count towards the quota set on the host.

Also, I think this is significant enough that you should list yourself in CONTRIBUTORS.markdown. 😉

[mohsenrezaeithe]

1. I prefer not to clutter the initial template, especially when the setting network_mode: might conflict with networks:.

Updated.

2. Perhaps we should warn that this might bypass quotas or firewalls for a specific network interface. For instance, the specially routed traffic might not count towards the quota set on the host.

I don't follow. I'm not familiar with any OS level quotas that'd affect this.

[favonia]

3. Perhaps we should warn that this might bypass quotas or firewalls for a specific network interface. For instance, the specially routed traffic might not count towards the quota set on the host.

I don't follow. I'm not familiar with any OS level quotas that'd affect this.

I wasn't being clear—I was talking about iptables and nftables. You can set up quotas or other rules on the host, and I believe macvlan will bypass them. In other words, the host (almost) can't see the traffic.

[mohsenrezaeithe]

I wasn't being clear—I was talking about iptables and nftables. You can set up quotas or other rules on the host, and I believe macvlan will bypass them. In other words, the host (almost) can't see the traffic.

Makes sense. I've added a note in the docs.

[favonia]

@mohsenrezaeithe Thank you for your contribution! ❤️