Not sure why it takes about 2 minutes for my desktop Thunderbird Email to connect to my MIAB server.
Problem just started in last few days.
The Web interface for Mail works perfectly and is very fast.
I am running on Vultr and have not seen this issue before. I get the same delay on port 465 and port 587.
Looks like a fail2ban/ufw throttle but I don’t see it.
Maybe I will turn on my ProtonVPN and hit my MIAB from another city or country.
Any suggestions would be really appreciated. This is a rock solid single purpose server.
Edit: Same delay issue when I access via VPN. So maybe not fail2ban.
Yikes. I solved this. My ISP at my home office is having trouble with IPv6. And DNSSEC appears to be the cause. So I am going to blame AWS because I use Route53 and DS records are very difficult to add/remote/edit.