So, if I run certbot on Server A to register some https:// URLs, do I certbot those same URLs again on Server B which is a mirror of Server A, or do I just copy the files?
I assume certbot registers them online and I would just need to copy the .pem files from Server A to B?
You should be able to do what you are proposing.
When we were working on a recent project, we had a Production server on a hosting platform, and a Test server in house. I was able to use certbot on the Production server to obtain the cert and then copied the relevant .pem files to the corresponding location on the Test server and it worked.
Just remember to copy the .pem files to Server B when they are renewed/updated 
Thank you! I’ll give that a try.
Maybe you know the answers to these related questions?
Is there a way to see which sites have been certified already so I don’t do them again?
Follow-up question, how does one delete a certificate? They say just don’t renew, but I’m set up to auto renew…
Oh! Must have missed this.
Perhaps it’d be better to have each server have it’s own cert since they’re set to auto-renew. Can there be multiple certs for the same URL?