Gather metrics from a Zyxel AX7501-B0 router

router-stats

#!/bin/bash
# Gather metrics from a Zyxel AX7501-B0 router and expose them in a Prometheus
# format.
#
# Usage:
# 1. create a user named "monitoring" (read-only access is sufficient)
# 2. change the password and IP address in this script down below
# 3. run this script
#
# Note that this script's output is ideally suited to be used in a
# textfile-collector of a Prometheus node exporter.
# For example, you can run this script periodically and redirect its output
# to a file, which can then be read by the Prometheus node exporter.

# We need this weird convolution, since the Zyxel device does not allow
# executing simple commands via SSH. It only allows running them from an
# interactive session, hence we force TTY allocation (via -t) and echo the
# command we would run to the shell.
echo -e "ifconfig\nexit" \
| sshpass -ppassword ssh -t [email protected] \
| sed -n '/^eth5\.3/,/^[^ ]/p' \
| sed -n 's/.*RX bytes[: ]\{1,\}\([0-9]\+\).*TX bytes[: ]\{1,\}\([0-9]\+\).*/router_bytes_received \1\nrouter_bytes_transmitted \2/p'