Thanks for the input, I think I am finally getting my head around this.
The CNAME record was actually already created for me and an example of it's use is here:
I don't think you understand me. You specified an HTTP URL (http://www.bbs.ch) and not a hostname (www.bbs.ch) as name of the CNAME. That is not a valid name for any hostname.
The part about the hosts filemane locally was about how computers behind a NAT resolve the "hostname" as per here:
However I can run DNS service on my local server so maybe it is better to set that up in one place to resolve all the internal addressing.
Ah, I see. Well, if your router does not support NAT loopback, then that sounds like a good idea. Beware, though, that it easily becomes confusing to maintain both local and public DNS zones for the same domain name. Personally, I prefer hosts files rather than local DNS services for public domains.
Once I read about port forwarding it made more sense, it does not matter of how many servers you pyhsically have, currently I have only one so I think the following is now correct.
Host TTL TYPE Data
bbs.ch 60 A 85.7.x.x
server001.bbs.ch 60 A 85.7.x.x
mail.bbs.ch 60 A 85.7.x.x
ftp.bbs.ch 60 A 85.7.x.x
http://www.bbs.ch 60 A bbs.ch
bbs.ch 3600 MX mail.bbs.ch
See the line I've outlined in bold. It should be something like
www.bbs.ch 60 CNAME bbs.ch
The TTL is a bit short. You would rarely benefit from having a very short TTL for a CNAME. I would rather set it to for example 3600 (1 hour).
Other than that, I notice that you have many A hosts pointing to the same IP. You can obviously have as many as you wish, but remember that you will have to keep each and every one up-to-date. I would rather recommend having only one or two A hosts, and let the others be CNAMEs that point to one of the A hosts. Just make sure the hostname you specify as your MX is an A host.
It is more about routing the service to the internal IP address so all of the services in this case would go to say 192.168.1.2 for example but in the future if I end up with a second server then some maybe routed to say 192.168.1.3
I think I have got that right. The reality as I think is that "Host" in this case is a human readable for an the "xxxx". in xxxx.bbs.ch is just really a label to make life easy, but generally they are indicative of the service they provide.
Can you tell me if my understanding is correct?
Yes, that sounds right. The public DNS system directs users on the Internet to your public IP (which belongs to your router). Your router is responsible for routing the traffic further to your internal devices. The DNS system is basically just an IP lookup service.