Enable / Disable access by port Debian / Apache

1

I am upgrading a Plone site on a 'server' that has Debian / Apache / Webmin.

I want to be able to enable / disable access by port number(s) ' while/when I work on it'.
Is there an easy way to do this without 'installing / configuring' too much ?

2

https://httpd.apache.org/docs/2.4/howto/access.html#env

3

Will this also work with http://m.y.i.p:portnumber/Plone (or is that not handled by apache?)

4

No.

but never expose outside direct Plone ports, use editor addresses, so you can close the editing part when needed.

For host ports, you've to use ipfilters, you can close the access (firewall like) to other ips other than your, for example.