Rookie Hostname/FQDN/DNS Questions

Question

Hello Everyone. 
 I am struggling is with Hostname/FQDN/DNS. I have read just about every thread with any of those words in the subject (including the zeroth rule and the DNS Best Practice thread) and I am not making any progress. I have a DynDNS account and I have set up the account in Network Services -> DNS - > DynDNS tab and it is correctly updating my dynamic public IP. I am able to ping my domain, but not the Sophos box. According to the instructions at Management -> System Settings -> Hostname tab: 
 
 My DynDNS hostname is "xxxx.is-a-geek.net" so in the Hostname field I entered "sophos.xxxx.is-a-geek.net". That make this the FQDN, right? I can ping 'xxxx.is-a-geek.net' and get a reply, but when I add 'sophos', I get 'ping request could not find sophos.xxxx.is-a-geek.net'. What else do I need to do in order to reach the FQDN? 
 
 Ultimately, I want to be able to use hostnames inside of my network to identify devices rather than the IP address, but I need to get all this hostname/fqdn/dns stuff sorted out first - it is the zeroeth rule after all. 
 In case it matters, my hardware is such: 
 
 I have some other questions about allowing/blocking traffic across these interfaces, but first the hostname thing needs fixed as I believe that I need that correct in order to be able to troubleshoot further configuration. 
 Thank you in advance for your assistance. 
 A little more about my setup as it applies to the DNS Best Practice thread: 
 
 All of my internal networks are listed on the 'Global' tab of 'Network Services >> DNS' 
 I have read conflicting ideas about how to set this up, but I think this is right: 
 I have not set this part up yet because I do not know if my internal DNS is set up correctly 
 This is the same as 3 - not sure if my internal DNS is set up correctly, but guidance here is appreciated 
 All of my internal networks provide their own DHCP, so I just set them to point back to themselves - again guidance here is appreciated 
 I do not understand this statement 
 and 8. I do not think apply 
 
 Sorry if this is a little scattered, but I think I may be in a little over my head and I am simply trying to explain everything to the best of my ability.

BAlfson · Accepted Answer

As I said above, Don, "The target for a Request Route must be a Network Host object, not any other Network object type." WebAdmin prevents many incorrect configurations. 
 If you don't have a local domain, you might want to adopt fisher.loc internally, for example. Then, in a Host definition, you could fill in a hostname like "laptop-don.fisher.loc" and complete the DHCP section so that the DHCP server always assigns your laptop the same IP. 
 Cheers - Bob

BAlfson · Answer

You can set a local domain in 'Remote Access >>Advanced', Don, and also in a DHCP Server definition. 
 Cheers - Bob

DKKDG · Answer

Hi Don, 
 the second hostname you want ping does not exist because there is no entry by your dnydns provider and your UTM does not create this entry. 
 Your UTM hostname is xxxx.is-a-geek.net and not sophos. xxxx.is-a-geek.net . If you want to use this name you have to create this dns entry at your dyndns provider. 
 For the dns best practice guide you can keep in mind the following order 
 - Clients ask internal DNS servers - DNS server asks UTM dns - UTM asks your prefered external DNS servers (shown in your last picture) 
 Also if you tick "Use forwarders assigned by ISP" your defined DNS Servers under forwarders will not be used by the UTM. The google DNS Servers are only an recommendation. 
 Best Regards DKKDG