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DNS Server question

JohnjonesJohnjones Member Posts: 105 ■■□□□□□□□□
When installing and configuring the first DNS server in an environment, what is the preferred and ALT DNS server? Should you just use Google's or ?

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    TheProfTheProf Users Awaiting Email Confirmation Posts: 331 ■■■■□□□□□□
    Well once you have your first DNS server, you can point it to itself and then use your router or an external server as your alternate DNS.
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    TechGuru80TechGuru80 Member Posts: 1,539 ■■■■■■□□□□
    Is this for a lab? The preferred is the first option and alternate obviously is the backup. The idea is when you push out dhcp information to clients, they rely on the dns server as their choice and the dns server has them configured to resolve. For a lab you can just use Google's dns servers.
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    JohnjonesJohnjones Member Posts: 105 ■■□□□□□□□□
    TheProf wrote: »
    Well once you have your first DNS server, you can point it to itself and then use your router or an external server as your alternate DNS.

    So the preferred is itself? How would it know where to look to resolve website requests?

    I'm setting up a lab and would use Google's public DNS for both PRI and ALT. But in a production information, how would you configure this?
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    TechGuru80TechGuru80 Member Posts: 1,539 ■■■■■■□□□□
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    OctalDumpOctalDump Member Posts: 1,722
    Are you talking about the DNS servers used by clients? If you want consistent resolution of internal names, then you should use internal DNS servers for all queries. This is particularly important in split DNS scenarios where you might have something like intranet.mycompany.com on the internal DNS servers, but not on the external servers, or have www.mycompany.com pointing at 192.168.1.45 on the internal server and 123.45.67.89 on the external server.

    If you give clients internal and external DNS servers, it can mean that internal resources are not always available to internal users.

    Fortunately, setting up multiple DNS servers with consistent records is fairly easy with Windows Server and AD integration.

    In general you treat the DNS servers' NICs DNS configuration the same as you would any other client, although generally you get them to use themselves first, since it is quicker.

    If you mean what you use as upstream resolvers for your DNS Servers, then you can use whatever you like, although closer DNS servers, such as your ISPs, are usually preferable.
    2017 Goals - Something Cisco, Something Linux, Agile PM
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    JohnjonesJohnjones Member Posts: 105 ■■□□□□□□□□
    OctalDump wrote: »
    Are you talking about the DNS servers used by clients? If you want consistent resolution of internal names, then you should use internal DNS servers for all queries. This is particularly important in split DNS scenarios where you might have something like intranet.mycompany.com on the internal DNS servers, but not on the external servers, or have www.mycompany.com pointing at 192.168.1.45 on the internal server and 123.45.67.89 on the external server.

    If you give clients internal and external DNS servers, it can mean that internal resources are not always available to internal users.

    Fortunately, setting up multiple DNS servers with consistent records is fairly easy with Windows Server and AD integration.

    In general you treat the DNS servers' NICs DNS configuration the same as you would any other client, although generally you get them to use themselves first, since it is quicker.

    If you mean what you use as upstream resolvers for your DNS Servers, then you can use whatever you like, although closer DNS servers, such as your ISPs, are usually preferable.

    Thanks for the reply.

    So say if I create a new DNS server, set the NIC configuration of DNS to 127.0.0.1 and leave the ALT field blank. I then proceed to configure my client workstation to use that lone DNS server and attempt to go to google.com - how would the DNS server know to get me there?

    My thinking was that the DNS server would need to be configured to another DNS server, say Google's for instance?

    Sorry I'm just trying to grasp the concepts. icon_smile.gif
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    OctalDumpOctalDump Member Posts: 1,722
    Yeah, you configure that within the DNS Service itself. The DNS Service can then direct clients (including the server the service is running on) to the upstream DNS servers. You want it to work this way so that your DNS service intercepts all DNS queries and can answer the ones it is authoritative for (or has cached).

    So, there are two ways to do this. You can simply forward to an external DNS server (or servers) in a "this is your problem now" kind of way, or you can use the root hints (the servers at the root of the DNS system and any others you add explicitly) so that queries start at the top of the food chain as it were. Usually, you do the former in smaller networks, or where you know that the upstream server is authoritative for particular domains of interest or you want to make advantage of that server's cache, and you do the latter when you have larger networks.

    Either way, the DNS settings for the server don't normally affect the operation of the DNS service.
    2017 Goals - Something Cisco, Something Linux, Agile PM
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