Dynamic DNS, DNS Records & Scavenging

Discussion in 'DNS Server' started by David, Apr 22, 2008.

  1. David

    David Guest

    Hi there,

    I posted this on the Server.general newsgroups but not heard anything back.
    Probably isn't the right newsgroup really. Thought i would try here to see
    if anyone can help;

    We have an issue whereby we want external clients to register there VPN IP
    addresses in DNS. The VPN connections are handled by a RAS server which gets
    the IP addresses from DHCP. There are two DHCP Servers;

    DC01 DHCP,DNS, Domain Controller

    Server01 DHCP,DNS, Domain Controller

    Server02 RAS

    Both the servers are set to update A and PTR records for clients. In DNS
    however this doesn't seem to be the case. I then added DC01 to the
    DNSUpdateProxy and when i did this i saw my test laptop register its ip in
    dns. I then disconnected and reconnected and got a different IP address. the
    ip address i got then was one which was already associated with an A record
    for another computer but the lease for the IP had expired hence why it was
    assigned to me. With the DHCP servers there are no overlaps in the IP
    address scopes. Do you think the A record for the other computer is stopping
    my system from registering a DNS record?

    Please note that there is no scavenging turned on at the server or the zone

    David, Apr 22, 2008
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  2. Read inline please.


    In my opinion, there is really no need for scavenging if the clients and the
    DHCP servers are properly configured.

    Have you created a new dedicated user account and configured the credentials
    into both DHCP servers?

    Here is a great article explaining how DHCP and DNS interact, and tells why
    you can disable DDNS on DHCP clients, you are basically making them act like
    Pre-Windows 2000 clients that cannot register in DNS.

    Using DNS servers with DHCP:
    http://technet2.microsoft.com/Windo...68-46c2-b017-caf25ae150ec1033.mspx?mfr=trueOn all networks I manage, I have cleared the "Register this connection'saddresses in DNS" check box on all DHCP addressed clients, and configuredDHCP to register for the clients. Doing this prevents the issue of oneclient updating a record registered by another DHCP client because all DHCPclients are registered by the DHCP server.Here are the recommended DHCP options I use.In addition use these Options,003 (router),006 (DNS Server),044 (WINS Servers)046 (Node type 0x8)015 (DNS Domain Name)I also have these Advanced DHCP options:001 Microsoft Windows 2000 Disable NetBIOS(0x0)002 Microsoft Windows 2000 Release DHCP lease on shutdown (0x1)On the DNS tab of the DHCP server properties sheet:3. Enable DNS updates according to the settings below:4. Always dynamically update DNS A and PTR records5. Discard A and PTR records when lease is deleted.6. Dynamically update DNS A and PTR records for DHCP clients that do notrequest updates (for example, clients running Windows NT4.0)This final setting is what allows clients that have DNS registrationsdisabled in TCP/IP on the DNS tab, to be registered in DNS.Advanced tab of DHCP propertiesClick the Credentials button and configure dedicated user account (Normaluser with no special privileges)These settings even allow my son's Xbox and my DirecTV HR20 DVR which runsLinux to be registered in DNS. (For whatever use it is, it just proves thatDHCP can register for Linux)--Best regards,Kevin D. Goodknecht Sr. [MVP]Hope This Helps===================================When responding to posts, please "Reply to Group"via your newsreader so that others may learn andbenefit from your issue, to respond directly tome remove the nospam. from my email address.===================================http://www.lonestaramerica.com/http...ftx.us/===================================Use Outlook Express?... Get OE_Quotefix:It will strip signature out and morehttp://home.in.tum.de/~jain/software/oe-quotefix/===================================Keep a back up of your OE settings and folderswith OEBackup:http://www.oehelp.com/OEBackup/Default.aspx===================================
    Kevin D. Goodknecht Sr. [MVP], Apr 22, 2008
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  3. David

    David Guest

    Hi Kevin,

    Thanks for your reply. I have set it up as described in the article and how
    you have set yours up. Unfortunately its still not updating records for
    remote VPN clients. Anyother thoughts.
    David, Apr 22, 2008
  4. David

    David Guest

    Shoud i Enable My RAS server as a LAN router as well?
    David, Apr 23, 2008
  5. Read inline please.

    Yes, you should.

    Best regards,
    Kevin D. Goodknecht Sr. [MVP]
    Hope This Helps

    When responding to posts, please "Reply to Group"
    via your newsreader so that others may learn and
    benefit from your issue, to respond directly to
    me remove the nospam. from my email address.
    Use Outlook Express?... Get OE_Quotefix:
    It will strip signature out and more
    Keep a back up of your OE settings and folders
    with OEBackup:
    Kevin D. Goodknecht Sr. [MVP], Apr 25, 2008
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