Thank you pititis...
That worked perfectly. I entered A records for mail, db, web, git, and also ns1, and ns2.
Maybe the problem was that I did not add A records for ns1 and ns2? I thought that was taken care of on the side of my host?
After entering the A records, I entered a CNAME record for www to web. Now I can do https://www.server.com:8080
ONE MORE QUESTION:
When creating a new website and new DNS records, how do I correctly point the user's site to mail.server.com?
Example: I create a domain for client.com. What will the DNS records look like for their email?