I\'ve recently tried running a cron job from within a linked docker container and run into an issue. My main docker container is linked to a postgres container and its port numb
I would recommend using declare
to export your environment and avoid escaping issues (use CMD or ENTRYPOINT or directly in a wrapper script which might be called by one of them):
declare -p | grep -Ev 'BASHOPTS|BASH_VERSINFO|EUID|PPID|SHELLOPTS|UID' > /container.env
Grep -v takes care of filtering out read-only variables.
You can later easily load this environment like this:
SHELL=/bin/bash
BASH_ENV=/container.env
* * * * * root /test-cron.sh