diff --git a/weave b/weave
index c50a1d6b..06dd7ba9 100755
--- a/weave
+++ b/weave
@@ -109,7 +109,7 @@ delete_iptables_rule() {
 create_bridge() {
     [ ! -d /sys/class/net/$BRIDGE ] && {
         ip link add name $BRIDGE type bridge
-        ip link set dev $BRIDGE address 7a:$(od -txC -An -N5 /dev/random | tr \  : | tail -c+2)
+        ip link set dev $BRIDGE address 7a:$(od -txC -An -N5 /dev/urandom | tr \  : | tail -c+2)
         # Attempting to set the bridge MTU to a high value directly
         # fails. Bridges take the lowest MTU of their interfaces. So
         # instead we create a temporary interface with the desired