diff --git a/lib/quantum b/lib/quantum
index ba98b64635..373d5217f6 100644
--- a/lib/quantum
+++ b/lib/quantum
@@ -6,6 +6,7 @@ XTRACE=$(set +o | grep xtrace)
 set +o xtrace
 
 export QUANTUM_TEST_CONFIG_FILE=${QUANTUM_TEST_CONFIG_FILE:-"/etc/quantum/debug.ini"}
+QUANTUM_AUTH_CACHE_DIR=${QUANTUM_AUTH_CACHE_DIR:-/var/cache/quantum}
 
 # Configures keystone integration for quantum service and agents
 function quantum_setup_keystone() {
@@ -22,6 +23,12 @@ function quantum_setup_keystone() {
     iniset $conf_file $section admin_tenant_name $SERVICE_TENANT_NAME
     iniset $conf_file $section admin_user $Q_ADMIN_USERNAME
     iniset $conf_file $section admin_password $SERVICE_PASSWORD
+    if [[ "$KEYSTONE_TOKEN_FORMAT" == "PKI" ]]; then
+        iniset $conf_file $section signing_dir $QUANTUM_AUTH_CACHE_DIR
+        # Create cache dir
+        sudo mkdir -p $QUANTUM_AUTH_CACHE_DIR
+        sudo chown `whoami` $QUANTUM_AUTH_CACHE_DIR
+    fi
 }
 
 function quantum_setup_ovs_bridge() {