I understand from this website https://tools.ietf.org/html/rfc6186 there is a way to add SRV record in DNS to autoconfigure email client with imap or pop. This should work in email clients like Thunderbird or Outlook. I know Exchange mailbox uses the autodiscover SRV record. I have a postfix server with multiple email domain, but only a certificate for the server domain. Let's say I have email.com and server.com. The certificate is only valid for the server.com. I would like to configure Thunderbird with the emailaddress [email protected]. Thunderbird should recognise there is a SRV record in DNS for imap and configure the incoming mailserver as server.com. The SRV record in DNS is: _submission._tcp.email.com. SRV 0 1 587 server.com. _imaps._tcp.email.com. SRV 0 1 993 server.com. Thurnderbird or Outlook resolves the emailaddress to email.com and not server.com. The problem is I'm getting a certificate warning. What I'm doing wrong? Maybe it is not supposed to work the way I think. Thanks, Edy
you'll want a cname for autoconfig in client domains dns, pointing to autoconfig.maindomain.tld a srv record for _autodiscover._tcp in client domains dns, pointing to autodiscover.maindomain.tld (port 443) and you'll want autoconfig and autodiscover A records in your main domains dns, pointing to the ip address of the autoconfig/autodiscover website. there's also a plugin to install in ispconfig. you can find more details about it all here: https://schaal-it.com/ispconfig-automail/ that said, I'm currently trying it all out myself and am having problems, I think I might need to contact them
