diff --git a/nixos/modules/tasks/network-interfaces.nix b/nixos/modules/tasks/network-interfaces.nix
index 20a740ce1f0..815523093dd 100644
--- a/nixos/modules/tasks/network-interfaces.nix
+++ b/nixos/modules/tasks/network-interfaces.nix
@@ -341,7 +341,7 @@ in
You should try to make this ID unique among your machines. You can
generate a random 32-bit ID using the following commands:
- cksum /etc/machine-id | while read c rest; do printf "%x" $c; done
+ head -c 8 /etc/machine-id
(this derives it from the machine-id that systemd generates) or