Help with DNS setup for LAN only

Question

I have a Mac Mini SNS 10.6.8 as our company's local standalone fileserver.
Everything has ran great for the past year (still is), but now I want to try and setup DNS for more control and services.
The server host name is servername (no FQDN), which shows up in Server Admin as servername.local.
I read and followed Hoffman Labs great step-by-step, but must have missed something, since I still cannot get DNS resolution.
Here is a brief summary of the Server Admin settings:
          Host Name                    servername
          Host (Server) IP          192.168.4.2
          Router IP (also default public DNS IP) 192.168.4.1
          Bonjour                    Wide Area  =  Not enabled
          Settings                    Accept recursive queries  =  localnets
          Settings                    Forwarder IPs  =  8.8.8.8  &  8.8.4.4  (Google Public DNS)
now...          Zones                              1 Primary Zone  =  companyname.net (we own the domain)
                                        Primary Zone Name  =  companyname.net
                                        Nameserver Zone  =  companyname.net
                                        Nameserver Host Name  =  servername.companyname.net
                                        2 A Records:
                                        servername          192.168.4.2
                                        user1                    192.168.4.3
                                        Reverse mapping - automatic - OK
Testing          Ran sudo changeip -checkhostname
                    Results:
                              Primary address          =          192.168.4.2
                              Current hostname          =          servername
                              The DNS hostname is not available. Please repair DNS and re-run this tool.
I must be doing something wrong, but I don't know what it is.  Please help.

Answer 1

Did you intend to have both "example.com" and "example.net" listed there?  Are those domains really different?  I'm going to assume that was an obfuscation error.  (This is part of the "fun" of obfuscation, unfortunately.  Of having to differentiate errors in the actual configuration from errors that were introduced during the obfuscation.)
>Oddly, even though I had manually assigned our Comcast gateway's DNS to Google DNS IPs, the gateway summary still shows up as Comcast's DNS server IPs.  So I removed the manually assigned Google DNS IPs from the gateway.
The gateway (or whatever you're using as your DHCP server) should be configured with the DNS server address of 192.168.4.2.  All other hosts on your network (if you're planning to use your local DNS everywhere on your LAN) should also reference 192.168.4.2, either through an explicit static configuration, or as the address that was received from the DHCP server.
And as for IP routing, are all your hosts, network printers, network gateways, DHCP servers, etc., all in the range of 192.168.4.1 to 192.168.4.254?  (They should be, if you're using a /24-class 255.255.255.0 subnet mask.)
But then I don't know where this configuration has gone off the rails...  (Over the years, I've seen and have made my own configuration errors, I've been "bagged" by DNS caches, and I've hit various bugs in DNS implementations.)  What you have stated here should work.
I'd start at the top of the DNS configuration article, and not stray from what is written there.   That there has been Google DNS and have had ISP DNS configured at the gateway does mean there were some areas that have strayed from the article.   I'd suggest following the DNS server configuration directions exactly.
Setting up DNS services with OS X Server isn't difficult, but it can be a little fussy. 
If you don't understand something that's written in that article -- or if you believe you need to enter something different than what's listed there -- then please stop and ask about it.  Either ask here, or ask over there.  (This feedback also helps improve that article.)
Straying from what's written in that article is certainly and entirely feasible, but that's something best left until after the adminstrator is more familiar with running a DNS server.  Once you know how and why and where you can stray, there are all sorts of things you can do within a DNS configuration.