import ./make-test-python.nix ({ pkgs, ... }: {
  name = "keepalived";

  nodes = {
    node1 = { pkgs, ... }: {
      networking.firewall.extraCommands = "iptables -A INPUT -p vrrp -j ACCEPT";
      services.keepalived.enable = true;
      services.keepalived.vrrpInstances.test = {
        interface = "eth1";
        state = "MASTER";
        priority = 50;
        virtualIps = [{ addr = "192.168.1.200"; }];
        virtualRouterId = 1;
      };
      environment.systemPackages = [ pkgs.tcpdump ];
    };
    node2 = { pkgs, ... }: {
      networking.firewall.extraCommands = "iptables -A INPUT -p vrrp -j ACCEPT";
      services.keepalived.enable = true;
      services.keepalived.vrrpInstances.test = {
        interface = "eth1";
        state = "MASTER";
        priority = 100;
        virtualIps = [{ addr = "192.168.1.200"; }];
        virtualRouterId = 1;
      };
      environment.systemPackages = [ pkgs.tcpdump ];
    };
  };

  testScript = ''
    # wait for boot time delay to pass
    for node in [node1, node2]:
        node.wait_until_succeeds(
            "systemctl show -p LastTriggerUSecMonotonic keepalived-boot-delay.timer | grep -vq 'LastTriggerUSecMonotonic=0'"
        )
        node.wait_for_unit("keepalived")
    node2.wait_until_succeeds("ip addr show dev eth1 | grep -q 192.168.1.200")
    node1.fail("ip addr show dev eth1 | grep -q 192.168.1.200")
    node1.succeed("ping -c1 192.168.1.200")
  '';
})