Commit 8615a25c authored by Kierán Meinhardt's avatar Kierán Meinhardt Committed by Kieran Meinhardt
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nixos/test-driver: make /etc/hosts VLAN-aware with primary IP fallback 

Resolves an issue where nodes on shared secondary VLANs could not reach
each other if their primary IPs were on isolated networks.
parent 7f6ea2a1

nixos/lib/testing/network.nix

+15 −6
Original line number Diff line number Diff line
@@ -64,11 +64,9 @@ let 
          optionalString (ipInterfaces != [ ])

            (head (head ipInterfaces).value.ipv6.addresses).address;



        # Generate /etc/hosts by only including IP addresses from VLANs that

        # both the local machine and the remote machine share. This prevents

        # machines from trying to connect via unreachable interfaces (e.g.,

        # a Management VLAN) and ensures name resolution matches the

        # actual network topology of the test.

        # Generate /etc/hosts including every remote's primary IP addresses

        # (whichever VLAN they may belong to) as well as all IP addresses from

        # VLANs that both the local machine and the remote machine share.

        networking.extraHosts =

          let

            localVlans = config.virtualisation.vlans;
@@ -91,13 +89,24 @@ let 
                    [ ]

                ) remoteInterfaces

              );



              # We also want to test router protocols that enable connections

              # between nodes even if they don't share a VLAN, so we include

              # the primary IPs of all machines in the hosts file.

              primaryIPs = [

                remoteConfig.networking.primaryIPAddress

                remoteConfig.networking.primaryIPv6Address

              ];



              allReachableIps = lib.lists.uniqueStrings (sharedIps ++ primaryIPs);



              hostnames =

                optionalString (

                  remoteConfig.networking.domain != null

                ) "${remoteConfig.networking.hostName}.${remoteConfig.networking.domain} "

                + "${remoteConfig.networking.hostName}\n";

            in

            builtins.concatStringsSep "" (map (ip: "${ip} ${hostnames}") sharedIps)

            builtins.concatStringsSep "" (map (ip: "${ip} ${hostnames}") allReachableIps)

          ) testModuleArgs.config.allMachines;

      };

    in