I’m not familiar with pkcs#12.
PKCS#12 is an archive file format, in this case used to bundle your private key and certificates.
I however have been using Letsencrypt to get
my free signed ssl certs for all my standalone and apache web servers.
How can I use does certs in Plex?
Edit: Available cert files from Letsencrypt: cert.pem chain.pem fullchain.pem privkey.pem
You’ll have to create a .pfx file (the PKCS#12 archive) containing both the private key and certificates of your chain. This is done using OpenSSL commands in your terminal:
openssl pkcs12 -export -in fullchain.pem -inkey privkey.pem -out archive.pfx -name "Name for Archive"
You’ll be prompted for a password, this password has to be filled in the Plex’ ‘Custom certificate encryption key’ field. I’m not sure if you had to password protect your private key upon Let’s Encrypt setup, you might be prompted for that as well.
After you’be obtained the .pfx file, store it on your media server computer (e.g. C:\SSL\archive.pfx). Then, occupy the ‘Custom certificate path’ field with the path to the file (C:\SSL\archive.pfx).
Last but not least, fill in the domain the certificate has been created for (e.g. plex.example.com 13).
A quick tip: in the ‘Remote Access’ setting, manually specify port 443 and update your router to point 443 external to 32400 internal. Then, for ‘Custom server access URLs’, fill in: https://plex.example.com:443 8.
You can now visit your custom SSL secured Plex domain using https://plex.example.com. Plex will do the rest. Try testing the domain outside your network the Plex server is hosted in, it might not work accessing the domain internally.
I forgot to mention here:
Last but not least, fill in the domain the certificate has been created for (e.g. plex.example.com 7).
That was ment for the ‘Custom certificate domain’ field.