#!/bin/bash
# long-running DB setup job
touch /var/run/db_freeze
trap 'rm -f /var/run/db_freeze' EXIT
do_stuff

#!/bin/bash
if [[ -f /var/run/db_freeze ]]; then
    #  Bail due to process lock from long-running job
    exit 2
fi
do_stuff
exit 0

#!/bin/bash
while [[ -f /var/run/db_freeze ]]; do
    sleep 30
done
do_stuff