DHCP reservation not register host name in DNS

When setting up a DHCP reservation, the hostname is required.

However, it's not resolvable in the local DNS server.

What's the point to define a host name in DHCP but not registered in DNS?

  • Please insert a picture of the edit of the configuration in question.

    Cheers - Bob

     
    Sophos UTM Community Moderator
    Sophos Certified Architect - UTM
    Sophos Certified Engineer - XG
    Gold Solution Partner since 2005
    MediaSoft, Inc. USA
  • Hello Dango,

    you are missing the domain-part to form a fully qualified domain name (FQDN) of your host.

    nslookup on a Windows system is looking for a "DNS-hostname" like this: you supply only the "hostname-part" like "prt1", then Windows looks for a DNS-suffix for that connection, then looks for a global DNS-suffix of the system. If it does not find one, it then tries to resolve the name with "NetBIOS over TCP" if this is enabled (normally, it is enabled by default). Lastly it would use the "hosts" file resolve.

    Only then you are succesfully able to resolve that crippled specification like "prt1".

    DNS NEEDS a domain-name to resolve, otherwise it would not find the right forward-zone to query. Do not confuse the DNS domain with your ADS-Domain, these are different things.

    So you need a complete hostname in a format like this: prt1.domain.local

    In your DHCP scope you can define "domain.local" to be handed out to your DHCP-clients, this is recommended.

    A Windows DHCP-Server automatically does, what you describe as "registering", if configured to do so.

    It hands out the DNS-suffix to the client and puts an A-record with the hostname in the corresponding forward zone of the DNS-server.

    Mit freundlichem Gruß, best regards from Germany,

    Philipp Rusch

    New Vision GmbH, Germany
    Sophos Silver-Partner

    If a post solves your question please use the 'Verify Answer' button.

  • Domain name is there in DHCP, trust me. It's a public one hence I don't want post here.

    DNS only resolve it when i manually add the FQDN. nslookup prt1 would resolve.

    My question here is why DHCP reservation require host name, but not add A record in DNS at the same time. What's the point of require host name in DHCP reservation without using it.

  • It looks like your prior participation was in the  XG (Sophos Firewall) Community instead of here in the UTM Community.  I can move this thread there, but it looks like you're not asking a question about either Sophos firewall, or???

    Cheers - Bob

     
    Sophos UTM Community Moderator
    Sophos Certified Architect - UTM
    Sophos Certified Engineer - XG
    Gold Solution Partner since 2005
    MediaSoft, Inc. USA
  • OK - I try to rephrase my explanations above: prt1 is not a complete hostname!

    This would be prt1.domain.local. Like dc1.newvision.local or file1.newvision.de but not just dc1 or file1.

    So the hostname you should have put into that reservation would be prt1.domain.local

    Or to be 100% exact: there has to be a "dot" at the end of each FQDN becaause the"." is the top level root domain.

    So it should be prt1.domain.local.

    Microsoft likes to leave things out for "comfort", but this is confusing people many times when they try to learn the norm.

    Mit freundlichem Gruß, best regards from Germany,

    Philipp Rusch

    New Vision GmbH, Germany
    Sophos Silver-Partner

    If a post solves your question please use the 'Verify Answer' button.