diff --git a/.github/workflows/main.yaml b/.github/workflows/main.yaml
index bed0ee6f2..35dd01c7a 100644
--- a/.github/workflows/main.yaml
+++ b/.github/workflows/main.yaml
@@ -73,15 +73,15 @@ jobs:
       - name: run python tests
         run: testing/python_test test_fot
       - name: setup fot stack
-        run: bin/setup_stack devices 5 skip-conn-check dhcp fot
+        run: bin/setup_stack devices 5 faux-mac-prefix "9a:99:57:1e" skip-conn-check dhcp fot
       - name: run fot integration tests
         run: timeout 20m bin/run_test_set fot
       - name: setup vxlan stack
-        run: bin/setup_stack devices 5 skip-conn-check dhcp fot vxlan
+        run: bin/setup_stack devices 5 faux-mac-prefix "9a:99:57:1e" skip-conn-check dhcp fot vxlan
       - name: run vxlan integration tests
         run: timeout 20m bin/run_test_set fot
       - name: setup dts
-        run: bin/setup_stack devices 5 skip-conn-check dhcp fot dts localhost
+        run: bin/setup_stack devices 5 faux-mac-prefix "9a:99:57:1e" skip-conn-check dhcp fot dts localhost
       - name: run dts integration tests
         run: timeout 20m bin/run_test_set fot
       - name: post-run logs
diff --git a/bin/run_controller b/bin/run_controller
index 19a4dc978..4d6a9b77d 100755
--- a/bin/run_controller
+++ b/bin/run_controller
@@ -116,7 +116,7 @@ if [ -n "$gauge_prom_pt" ]; then
 fi
 
 forch_port="-p 500$faucet_id:9019"
-docker_envs="--env RUN_MODE=$run_mode"
+docker_envs="--env RUN_MODE=$run_mode --env CLEAN_MAC_PREFIX=$CLEAN_MAC_PREFIX"
 
 if [[ -n $vxlan ]]; then
     # Extract the local src IP address that can be used as return address.
diff --git a/bin/run_faux b/bin/run_faux
index 422887cb9..4d1f0c9ef 100755
--- a/bin/run_faux
+++ b/bin/run_faux
@@ -2,13 +2,16 @@
 
 ROOT=$(realpath $(dirname $0)/..)
 postfix=
-intf_mac=9a:02:57:1e:8f:00
 docker_args=
 container_prefix=forch-faux
 image=forch/faux
 net_opt=--net=none
 port_num=0
 
+source bin/stack_functions
+set_faux_mac_prefix
+
+intf_mac=$FAUX_MAC_PREFIX:8f:00
 cd $ROOT
 
 # If the first argument is a number, then it's a port designation.
@@ -22,10 +25,9 @@ if [ $# -gt 0 ] && [ $(($1)) -gt 0 -o "$1" == 0 ]; then
         mac_port_num=$port_num
     fi
     postfix=-$port_num
-    intf_mac=9a:02:57:1e:$(printf %02x $mac_prefix):$(printf %02x $mac_port_num)
+    intf_mac=$FAUX_MAC_PREFIX:$(printf %02x $mac_prefix):$(printf %02x $mac_port_num)
     shift
 fi
-
 FAUX_ARGS="$*"
 
 # Check that image exists so docker doesn't pull down random one from dockerhub
@@ -42,14 +44,14 @@ fi
 
 docker_args="$docker_args -e LOCAL_IF=$realintf -e FAUX_NUM=$port_num"
 
-cid=$(docker run -d --privileged --name $CONTAINER --hostname $CONTAINER $net_opt $docker_args $image ./start_faux $FAUX_ARGS)
+cid=$(docker run -d --privileged --name $CONTAINER --hostname $CONTAINER $net_opt $docker_args $image ./start_faux $FAUX_ARGS "faux-mac-prefix=$FAUX_MAC_PREFIX" )
 pid=$(docker inspect --format="{{ .State.Pid }}" $cid)
 
 intf=faux$postfix
 echo Removing old interface $intf
 sudo ip link del $intf 2>/dev/null || true
 
-echo Adding new interface to $pid...
+echo Adding new interface $intf_mac to $pid...
 sudo ip link add $intf type veth peer name faux-eth0 addr $intf_mac netns $pid
 sudo ip link set $intf up
 
diff --git a/bin/setup_scale b/bin/setup_scale
index 6fb66f28b..34929050b 100755
--- a/bin/setup_scale
+++ b/bin/setup_scale
@@ -40,6 +40,7 @@ if [ -n "$1" ]; then
 fi
 
 source bin/stack_functions
+set_faux_mac_prefix
 
 ###########################################################
 
diff --git a/bin/setup_stack b/bin/setup_stack
index abf09cfdc..086da8d3a 100755
--- a/bin/setup_stack
+++ b/bin/setup_stack
@@ -27,6 +27,11 @@ if [ "$1" == "devices" ]; then
     shift 2
 fi
 
+if [ "$1" == "faux-mac-prefix" ]; then
+    export FAUX_MAC_PREFIX="$2"
+    shift 2
+fi
+
 if [ "$1" == "switches" ]; then
     switches=$2
     shift 2
@@ -89,6 +94,7 @@ fi
 
 rm -rf tcpdump # Clean out directory
 source bin/stack_functions
+set_faux_mac_prefix
 
 ###########################################################
 
@@ -173,6 +179,9 @@ if [ -z "$remote" ]; then
 
     cp topo/$mode/forch/* $container_inst/forch/
     cp topo/$mode/faucet/* $container_inst/faucet/
+
+    find $container_inst/ -name *.yaml -exec sed -i "s/$DEFAULT_MAC_PREFIX/$FAUX_MAC_PREFIX/" {} \;
+
     docker kill $container || true
 
     if [ -n "$fot" ]; then
diff --git a/bin/stack_functions b/bin/stack_functions
index 475972993..17afe7ac8 100644
--- a/bin/stack_functions
+++ b/bin/stack_functions
@@ -119,6 +119,23 @@ function add_oeth {
     sudo ovs-vsctl add-port $br_a $iface_a -- set interface $iface_a ofport_request=$pt_a
 }
 
+function set_faux_mac_prefix {
+    export DEFAULT_MAC_PREFIX="9a:02:57:1e"
+    export DEFAULT_CLEAN_MAC_PREFIX="9a02571e"
+    if [ -z $FAUX_MAC_PREFIX ]; then
+        FAUX_MAC_PREFIX=$DEFAULT_MAC_PREFIX
+    fi
+
+    correct_mac_prefix=`echo $FAUX_MAC_PREFIX  | egrep '([0-9a-zA-Z]{2}:){3}[0-9a-zA-Z]{2}'`
+    if [ -z $correct_mac_prefix ]; then
+        echo "$FAUX_MAC_PREFIX is an invalid mac prefix. FAUX_MAC_PREFIX should be in the format 'XX:XX:XX:XX'"
+        false
+    fi
+    CLEAN_MAC_PREFIX=`echo $FAUX_MAC_PREFIX | sed 's/://g'`
+    export FAUX_MAC_PREFIX=$FAUX_MAC_PREFIX
+    export CLEAN_MAC_PREFIX=$CLEAN_MAC_PREFIX
+}
+
 function add_faux {
     switch=$1
     port=$2
diff --git a/controller/bin/controller_go b/controller/bin/controller_go
index 87c430744..f168eb537 100755
--- a/controller/bin/controller_go
+++ b/controller/bin/controller_go
@@ -83,6 +83,10 @@ else
     ifconfig data0 up
 fi
 
+if [ -n "$CLEAN_MAC_PREFIX" ]; then
+    bin/rename_site_config $CLEAN_MAC_PREFIX
+fi
+
 echo Forch config
 cat $FORCH_CONFIG
 
diff --git a/controller/bin/rename_site_config b/controller/bin/rename_site_config
new file mode 100755
index 000000000..35e0ba817
--- /dev/null
+++ b/controller/bin/rename_site_config
@@ -0,0 +1,9 @@
+#!/bin/sh
+
+default_mac_prefix="9a02571e"
+
+if [ "$1" != $default_mac_prefix ]; then
+    for f in `find /site/mac_addrs/ -name "$default_mac_prefix*"`; do
+        cp -r $f `echo $f | sed -e "s/$default_mac_prefix/$1/g"`
+    done
+fi
diff --git a/etc/start_faux b/etc/start_faux
index c38d56e82..0eb3ea200 100755
--- a/etc/start_faux
+++ b/etc/start_faux
@@ -17,11 +17,13 @@ for option in $*; do
 done
 
 IFACE=faux-eth0
+FAUX_MAC_PREFIX="${options['faux-mac-prefix']}"
 PREFIX=$(($FAUX_NUM/256 + 1))
 SUFFIX=$(($FAUX_NUM%256))
 IPADDR=192.168.$PREFIX.$SUFFIX
 GATEWAY=192.168.1.0
 
+echo $FAUX_MAC_PREFIX
 while ! ip link show $IFACE; do
     sleep 2
 done
@@ -42,7 +44,7 @@ else
     ip route add default via $GATEWAY
 fi
 
-if [ -n "${option[ping]}" ]; then
+if [ -n "${options[ping]}" ]; then
     ping -c 10 $GATEWAY &
 fi
 
@@ -52,8 +54,8 @@ ip route
 if [ -n "${options[dnsmasq]}" ]; then
     echo Configuring dnsmasq...
     echo dhcp-range=192.168.1.10,192.168.1.255 >> /etc/dnsmasq.conf
-    echo dhcp-host=9a:02:57:1e:8f:01,192.168.1.1 >> /etc/dnsmasq.conf
-    echo dhcp-host=9a:02:57:1e:8f:02,192.168.1.2 >> /etc/dnsmasq.conf
+    echo dhcp-host=$FAUX_MAC_PREFIX:8f:01,192.168.1.1 >> /etc/dnsmasq.conf
+    echo dhcp-host=$FAUX_MAC_PREFIX:8f:02,192.168.1.2 >> /etc/dnsmasq.conf
     dnsmasq --log-facility=/tmp/dnsmasq.log --log-dhcp
 fi
 
diff --git a/etc/test_fot.out b/etc/test_fot.out
index 885a33058..3595d71cf 100644
--- a/etc/test_fot.out
+++ b/etc/test_fot.out
@@ -8,9 +8,9 @@ Device 04 log count 0
 275
 100
 274
-9a02571e8f01: []
-9a02571e8f02: []
-9a02571e8f03: ['9a02571e8f03:hold:DaqException']
-9a02571e8f05: ['9a02571e8f05:hold:DaqException']
+9a99571e8f01: []
+9a99571e8f02: []
+9a99571e8f03: ['9a99571e8f03:hold:DaqException']
+9a99571e8f05: ['9a99571e8f05:hold:DaqException']
 5 packets transmitted, 5 received, 0% packet loss, XXX
 5 packets transmitted, 0 received, XX errors, 100% packet loss, XXX
diff --git a/testing/test_fot b/testing/test_fot
index 25b91e9fc..25cd118b8 100755
--- a/testing/test_fot
+++ b/testing/test_fot
@@ -76,30 +76,30 @@ vlan=$($YQ '.dps."nz-kiwi-t2sw1".interfaces."1".native_vlan' $BEHAVIORAL_CONFIG)
 echo $(( (vlan > 271) + (vlan > 276) )) | tee -a $TEST_RESULTS
 echo $(( (vlan > 271) + (vlan > 276) )) | tee -a $TEST_RESULTS
 
-monitor_daq_log "Send device result 9a:02:57:1e:8f:01 passed"
-monitor_daq_log "Send device result 9a:02:57:1e:8f:02 failed"
-monitor_daq_log "Target device 9a02571e8f03 test hold running"
-monitor_daq_log "Target device 9a02571e8f05 test hold running"
+monitor_daq_log "Send device result 9a:99:57:1e:8f:01 passed"
+monitor_daq_log "Send device result 9a:99:57:1e:8f:02 failed"
+monitor_daq_log "Target device 9a99571e8f03 test hold running"
+monitor_daq_log "Target device 9a99571e8f05 test hold running"
 
 echo `timestamp` stopping forch-faux-3
 docker stop forch-faux-3 # Remove device 3 to generate port-down event.
 
-log_count=$(fgrep "9a:02:57:1e:8f:04" $DAQ_BASE/cmdrun.log | wc -l)
+log_count=$(fgrep "9a:99:57:1e:8f:04" $DAQ_BASE/cmdrun.log | wc -l)
 echo Device 04 log count $log_count | tee -a $TEST_RESULTS
 
 report_vlans
 
-monitor_forch_log "Device 9a:02:57:1e:8f:04 is entering operational state from unauthenticated state"
+monitor_forch_log "Device 9a:99:57:1e:8f:04 is entering operational state from unauthenticated state"
 
 # Check if it's running in client/server or server/client mode and adjust expectations accordingly.
 sserv_mode=$(fgrep ssserv $DAQ_BASE/cmdrun.log | wc -l)
 if [[ $sserv_mode == 0 ]]; then
-    monitor_daq_log "Remaining target sets: \[9a02571e8f05\]"
+    monitor_daq_log "Remaining target sets: \[9a99571e8f05\]"
     expected_timeouts=0
     # Device 8f:05 doesn't timeout in this mode, so add artificial result for later on.
-    echo "9a02571e8f05: ['9a02571e8f05:hold:DaqException']" | sudo tee -a $DAQ_BASE/result.log
+    echo "9a99571e8f05: ['9a99571e8f05:hold:DaqException']" | sudo tee -a $DAQ_BASE/result.log
 else
-    monitor_forch_log "Device 9a:02:57:1e:8f:03 disconnected"
+    monitor_forch_log "Device 9a:99:57:1e:8f:03 disconnected"
     monitor_daq_log "Remaining target sets: \[\]"
     expected_timeouts=2
 fi
diff --git a/topo/dva/forch/behaviors.yaml b/topo/dva/forch/behaviors.yaml
index 10ba4f6ea..7105f0903 100644
--- a/topo/dva/forch/behaviors.yaml
+++ b/topo/dva/forch/behaviors.yaml
@@ -1,5 +1,5 @@
 device_mac_behaviors:
-  "9A:02:57:1E:8F:01":
+  "9a:02:57:1e:8f:01":
     segment: INFRA
     role: hello_world.foo.bar#bazqux@quuxquuz123
   "02:03:04:00:00:03":