From 27b8253655217f46532625d07fb8d4cdbd649489 Mon Sep 17 00:00:00 2001
From: Daniel Fullmer <danielrf12@gmail.com>
Date: Thu, 9 Jan 2020 17:34:54 -0500
Subject: [PATCH] nixos/zerotierone: prevent systemd from changing MAC address

---
 nixos/modules/services/networking/zerotierone.nix | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/nixos/modules/services/networking/zerotierone.nix b/nixos/modules/services/networking/zerotierone.nix
index 764af3846fe5..190ffdf4cad3 100644
--- a/nixos/modules/services/networking/zerotierone.nix
+++ b/nixos/modules/services/networking/zerotierone.nix
@@ -63,5 +63,15 @@ in
     networking.firewall.allowedUDPPorts = [ cfg.port ];
 
     environment.systemPackages = [ cfg.package ];
+
+    # Prevent systemd from potentially changing the MAC address
+    environment.etc."systemd/network/50-zerotier.link".text = ''
+      [Match]
+      OriginalName=zt*
+
+      [Link]
+      AutoNegotiation=false
+      MACAddressPolicy=none
+    '';
   };
 }