diff --git a/impl/setup_tundev.sh b/impl/setup_tundev.sh
index eef4411..bdd3f8c 100755
--- a/impl/setup_tundev.sh
+++ b/impl/setup_tundev.sh
@@ -9,8 +9,10 @@ fi
 
 set -euo pipefail
 
+HOSTID="$1"
+
 DEV=hamnet70
 
 sudo ip tuntap add dev $DEV mode tun user $(whoami)
 sudo ip link set dev $DEV up
-sudo ip address add dev $DEV 10.99.99.1/24
+sudo ip address add dev $DEV fd73::$HOSTID/64