I’m needing to generate certs for 3rd parties, ie cdn.mycustomer1.com, cdn.mycustomer2.org. I would like to use SAN certs to keep the number of certs I need to load into my server software minimal.
If I have 100 new customers every week, I can easily generate individual certs for them as I understand it. But how would I do it so they were part of a SAN cert? I’d run into rate limits if I tried it, no?
You can certainly issue a certificate containing hostnames from 100 different domains.
But doing so increments the “20 certificates per domain per week” limit for each of those 100 domains, so you couldn’t issue up to 100 certificates for the same (growing) set of names a week.
I might suggest a compromise. Something like:
When a new customer signs up, issue a certificate with just their name.
Once a day, issue a certificate with all of that day’s customers combined, and discard their individual certificates.
Once a week, issue a certificate with all of that week’s customers combined, discarding the 7 daily certificates.
That would still limit the number of certificates you manage, while only dinging each domain 3 times in a week.
Alternately, go all out, and use a software stack that’s fine with having tons of certificates under management.
Alternately alternately, use a different CA with high prices and high rate limits.