Adding Let's Encrypt to postfix/dovecot

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1

I’m trying to add a ssl cert to postfix/dovecot.

Current setup:
host1.serverdomain.com (Not on Virtualmin)
domain.com (Already has Let’s Encrypt cert)

I tried adding the servers domain to virtualmin to auto add the cert but domain.com starts using the host1.serverdomain.com ssl cert.

How do I fix this?

One external IPv4 address
Ubuntu Linux 14.04.3
Webmin version 1.791
Virtualmin version 5.01.gpl

2

You can request the cert for hostname using Webmin Configuration > SSL Settings > Lets Encrypt.
In Lets Encrypt you have to manually type domain name as hostname and doc root “/var/www/html/”
The it will install a cert for webmin. You can then give postfix, dovecot the paths to cert,key and ca files

3

Thank you for the response. I was able to create the cert and link to the files, however, imap/smtp show “The certificate is not trusted because it hasn’t been verified as issued by a trusted authority using a secure signature.”. EDIT: Is the letsencrypt-ca.pem file, the same as chain.pem?

Also, is it possible to link mail.domain.com to hostname?

mail.domain.com. CNAME hostname. domain.com. IN MX 5 hostname. domain.com. IN TXT "v=spf1 a mx a:domain.com ip4:123.123.123.123 ?all"
4

You probably need to use the fullchain.pem file to also serve the intermediate certificate (letsencrypt X3 or so). The file can be found at /etc/letsencrypt/host.domain.tld/.