diff --git a/network.sh b/network.sh
index db4ca54..88a8627 100644
--- a/network.sh
+++ b/network.sh
@@ -2,8 +2,8 @@
 set -eu
 
 : ${VM_NET_TAP:=''}
-: ${VM_NET_MAC:=''}
 : ${VM_NET_IP:='20.20.20.21'}
+: ${VM_NET_MAC:='82:cf:d0:5e:57:66'}
 
 : ${DNS_SERVERS:=''}
 : ${DNSMASQ:='/usr/sbin/dnsmasq'}