On Sat, Jun 18, 2022 at 09:05:07AM +1000, raf wrote: > Even if the middle pair were in the right order, and > even if they successfully replaced the first pair (which > might not be a thing anyway), it would still end up with > a single RSA certificate, not both.
Correct. For multiple MTA personalities there's SNI (generally not a good practice, we have MX records for serving multiple domains on a single SMTP server). This requires lookup tables that map various names to non-default certificate chains. -- Viktor.