diff --git a/ctdb/config/functions b/ctdb/config/functions
index 09b32097e01..7a47c9d8e79 100755
--- a/ctdb/config/functions
+++ b/ctdb/config/functions
@@ -867,8 +867,8 @@ if ! type mktemp >/dev/null 2>&1 ; then
 	fi
 	_d="${TMPDIR:-/tmp}"
 	_hex10=$(dd if=/dev/urandom count=20 2>/dev/null | \
-	    md5sum | \
-	    sed -e 's@\(..........\).*@\1@')
+	    cksum | \
+	    awk '{print $1}')
 	_t="${_d}/tmp.${_hex10}"
 	(
 	    umask 077
diff --git a/ctdb/tests/eventscripts/scripts/11.natgw.sh b/ctdb/tests/eventscripts/scripts/11.natgw.sh
index 1bdcb690b15..75b2771899c 100644
--- a/ctdb/tests/eventscripts/scripts/11.natgw.sh
+++ b/ctdb/tests/eventscripts/scripts/11.natgw.sh
@@ -46,8 +46,8 @@ EOF
 ok_natgw_master_ip_addr_show ()
 {
 	_mac=$(echo "$CTDB_NATGW_PUBLIC_IFACE" |
-	       md5sum |
-	       sed -r -e 's@(..)(..)(..)(..)(..)(..).*@\1:\2:\3:\4:\5:\6@')
+	       cksum |
+	       sed -r -e 's@(..)(..)(..).*@fe:fe:fe:\1:\2:\3@')
 
 	# This is based on CTDB_NATGW_PUBLIC_IP
 	_brd="10.1.1.255"
@@ -63,8 +63,8 @@ EOF
 ok_natgw_slave_ip_addr_show ()
 {
 	_mac=$(echo "$CTDB_NATGW_PUBLIC_IFACE" |
-	       md5sum |
-	       sed -r -e 's@(..)(..)(..)(..)(..)(..).*@\1:\2:\3:\4:\5:\6@')
+	       cksum |
+	       sed -r -e 's@(..)(..)(..).*@fe:fe:fe:\1:\2:\3@')
 
 	ok <<EOF
 1: ${CTDB_NATGW_PUBLIC_IFACE}: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
diff --git a/ctdb/tests/eventscripts/stubs/ip b/ctdb/tests/eventscripts/stubs/ip
index 1c4ad35b50a..630d0e8b433 100755
--- a/ctdb/tests/eventscripts/stubs/ip
+++ b/ctdb/tests/eventscripts/stubs/ip
@@ -124,7 +124,7 @@ ip_link_show ()
 	    _opts="<LOOPBACK${_flags}> mtu 65536 qdisc noqueue state UNKNOWN"
 	    ;;
     *)
-	    _mac=$(echo $dev | md5sum | sed -r -e 's@(..)(..)(..)(..)(..)(..).*@\1:\2:\3:\4:\5:\6@')
+	    _mac=$(echo $dev | cksum | sed -r -e 's@(..)(..)(..).*@fe:fe:fe:\1:\2:\3@')
 	    _brd="ff:ff:ff:ff:ff:ff"
 	    _type="ether"
 	    _opts="<BROADCAST,MULTICAST${_flags}> mtu 1500 qdisc pfifo_fast state ${_state} qlen 1000"