+usage() {
+ cat <<EOF
+$(basename $0) - build NFVbench VM images
+Usage:
+ $(basename $0) [OPTIONS]
+
+OPTIONS
+ -l: build NFVbench loop VM image
+ -g: build NFVbench generator image
+ -v: verify only (build but do not push to google storage)
+
+ -t: enable debug trace (set -x + DIB_DEBUG_TRACE=1)
+ -d: start debug shell in image chroot in case of build error
+ -h: show this help message
+EOF
+ exit 1
+}
+
+while getopts ":lgvtdh" opt; do