diff --git a/usr/local/share/bastille/clone.sh b/usr/local/share/bastille/clone.sh
index f26f460a..e11bd701 100644
--- a/usr/local/share/bastille/clone.sh
+++ b/usr/local/share/bastille/clone.sh
@@ -126,8 +126,8 @@ update_jailconf_vnet() {
                     sed -i '' "s|e\([0-9]\{1,\}\)b_${NEWNAME}|e${uniq_epair_bridge}b_${NEWNAME}|g" "${JAIL_CONFIG}"
                     sed -i '' "s|epair\([0-9]\{1,\}\)|epair${uniq_epair_bridge}|g" "${JAIL_CONFIG}"
 		    sed -i '' "s|exec.prestart += \"ifconfig e0a_bastille\([0-9]\{1,\}\).*description.*|exec.prestart += \"ifconfig e0a_${uniq_epair} description \\\\\"vnet host interface for Bastille jail ${NEWNAME}\\\\\"\";|" "${JAIL_CONFIG}"
-                    sed -i '' "s|ether.*:.*:.*:.*:.*:.*a |ether ${macaddr}a |" "${JAIL_CONFIG}"
-                    sed -i '' "s|ether.*:.*:.*:.*:.*:.*b |ether ${macaddr}b |" "${JAIL_CONFIG}"
+                    sed -i '' "s|ether.*:.*:.*:.*:.*:.*a\";|ether ${macaddr}a\";|" "${JAIL_CONFIG}"
+                    sed -i '' "s|ether.*:.*:.*:.*:.*:.*b\";|ether ${macaddr}b\";|" "${JAIL_CONFIG}"
                     break
                 fi
             fi
diff --git a/usr/local/share/bastille/common.sh b/usr/local/share/bastille/common.sh
index da03dc3f..b9b0986f 100644
--- a/usr/local/share/bastille/common.sh
+++ b/usr/local/share/bastille/common.sh
@@ -110,9 +110,14 @@ check_target_is_stopped() {
 generate_static_mac() {
     local jail_name="${1}"
     local external_interface="${2}"
-    local macaddr_prefix="$(ifconfig ${external_interface} | grep ether | awk '{print $2}' | cut -d':' -f1-3)"
-    local macaddr_suffix="$(echo -n ${jail_name} | sha256 | cut -b -5 | sed 's/\([0-9a-fA-F][0-9a-fA-F]\)\([0-9a-fA-F][0-9a-fA-F]\)\([0-9a-fA-F]\)/\1:\2:\3/')"
+    local external_interface_mac="$(ifconfig ${external_interface} | grep ether | awk '{print $2}' | sed 's#:##g')"
+    local macaddr_prefix="$(echo -n "${external_interface_mac}" | sha256 | cut -b -6 | sed 's/\([0-9a-fA-F][0-9a-fA-F]\)\([0-9a-fA-F][0-9a-fA-F]\)\([0-9a-fA-F]\)/\1:\2:\3/')"
+    local macaddr_suffix="$(echo -n "${jail_name}" | sha256 | cut -b -5 | sed 's/\([0-9a-fA-F][0-9a-fA-F]\)\([0-9a-fA-F][0-9a-fA-F]\)\([0-9a-fA-F]\)/\1:\2:\3/')"
+    if [ -z "${macaddr_prefix}" ] || [ -z "${macaddr_suffix}" ]; then
+        error_notify "Failed to generate MAC address."
+    fi
     macaddr="${macaddr_prefix}:${macaddr_suffix}"
+    export macaddr
 }
 
 generate_vnet_jail_netblock() {