adds ssh tunneling script to connect remote DB

env_files/ssh-tunnel-example.env

+local_ip=192.168.2.109
+local_ip_on_remote=localhost
+local_port=5432
+local_port_on_remote=5432
+remote_host=federal-non-interactive

start-ssh-tunnel.sh

+#! /bin/sh
+#
+
+if [ "$#" -eq 0 ] || [ "$#" -gt 1 ]; then
+  echo takes only one argument
+  exit 1
+fi
+
+if [ ! -e "${1}" ]; then
+  echo cannot find "${1}"
+  exit 1
+fi
+
+# shellcheck source=./env_files/ssh-tunnel-example.env
+. "${1}"
+
+ssh \
+  -v \
+  -N \
+  -L \
+  "${local_ip}:${local_port}:${local_ip_on_remote}:${local_port_on_remote}" \
+  "${remote_host}"