This whitelist is 1409 records long, so indeed as you say very small. I
suppose I could download it and host it locally. Apparently AXFR is not
allowed, but plain text HTTP download is, so that's good enough.
Then I would only need an efficient and robust way for postfix to use
it.
If they let you download a list of IPs, just use your favorite
sed/awk/perl to change it into an access table.
The question is: Will this be really more reliable than using a policy
service that simply queries dns for this task?
