Migration from Windows to Linux

[rg305]

@super

the same cert

@rg305

Let's get these out in the clear:

• what defines a cert is not the list of covered names
  each cert has an individual number
  more than one cert can exist with the exact same set of covered names
• if a cert is renewed on system one, then it doesn't need to be renewed on system two
  the new cert on system one can be copied to system two and also used there
  if the cert is renewed on both systems, then they no longer have the exact same cert
  they will then have two similar certs - but not the same one

[schoen]

@super

So it sounds like there are no command line options that can re-request the same cert as one that had just been renewed?

The different machines are not sufficiently aware of one another's certificate issuance activity to make this feasible.

You could actually imagine a setup where something like this would happen, but it would have to use the Certificate Transparency system to learn about the issuance requested by the other machine. Currently no Let's Encrypt client makes use of that information, so none has a way to refer to the contents of certificates requested for the same names or services by a different machine.