How to share the apt cache

Hi. We use Debian on a number of machines, and, to avoid downloading the
same packages multiple times, we download debian cd images (which are kept
updated with jigdo) to a server and set sources.list to point (only) to this
images.

But this has obvious problems.
What is the "correct" way to share the apt cache? I think we should keep
/var/cache/apt/archives in the server and mount it with nfs in the other
computers. But I'm not shure this is the "correct" way; I don't know enough
about the behaviour of apt to be sure that this won't bring an obscure
problem. What should I do?

Thank you.

--
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