DefGuard / defguard

Enterprise, fast, secure VPN & SSO platform with hardware keys, 2FA/MFA
https://defguard.net
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Conflicts in network addresses across locations are not detected (bug/enhancement) #614

Open dbutti opened 2 months ago

dbutti commented 2 months ago

Describe the bug If two or more VPN locations use the same IP network address, a conflict arises if the corresponding tunnels are connected simultaneously

To Reproduce Steps to reproduce the behavior:

  1. Create two VPN locations
  2. Assign (unique) gateway IP addresses but on the same network
  3. Connect a Defguard client to both locations at the same time (nothing stops you from doing so)
  4. In the best case only 1 tunnel will work. Conflicts may also arise in the assignment of IP addresses to the clients

Expected behavior/enhancement Defguard considers every VPN location as a completely independent realm, where no coordination in the assignment of IP addresses is attempted, and under the silent assumption that locations using the same VPN IP netmask are not to be connected to simultaneously. This can be a valid use case, but the situation where several VPN locations could be sharing the same VPN IP network are valid (and very useful), too.

For instance, I frequently use Wireguard to set up a pattern manually where:

In this way, the client can access several parts of a distributed infrastructure by using a single wireguard interface, which simplifies management and reduces the number of addresses/networks to handle.

This use case could be easily supported by Defguard if:

I hope my description is clear enough; please feel free to contact me in case additional information is needed (also on matrix: @dbutti:matrix.neaweb.ch)

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