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intermittent problem with resolving hosts on conditional forward domain RRS feed

  • Question

  • We have a trust established between domain A and Domain B. Domain B is our local domain with all local users computers(windows 7) and a domain controller(server 2008 R2) and Domain A is hosted servers( all server 2012 R2 VM's) from a hosting provider on the internet. We have a site to site VPN established between the 2 domains. Domain A consists of a Domain Controller, database server and 2 Remote Desktop servers. so Users in Domain B rdp to one of the 2 terminal servers in Domain A.

    On Domain B's domain controller is also our DNS server which has a conditional forwarder setup to the IP Address of Domain A's Domain controller/DNS server.

    occasionally the local workstations on Domain B lose connection to the Remote Desktop Servers on Domain A and the problem is that the hostname of the Remote Desktop Servers cannot be resolved locally. for example when the problem occurs on a local computer on Domain B i can ping the IP address of the remote desktop server on domain A but cannot ping or nslookup the hostname, whether fully qualified or not. I can ping and nslookup the Domain Controllers hostname and the database server on Domain A so it's not a VPN failure or that domain A's DNS server is not responding it just seems to be 1 of the 2 remote desktop servers cannot be resolved.

    A ping -a of the IP address of Domain A remote desktop server from Domain B comes back with the correct hostname. this happens on all computers and servers in Domain B for about 10 minutes and then seems to resolve itself without any intervention. I used to think that flushing the DNS cache was resolving the problem but the last 2 instances when this happened i was not able to connect quick enough and the problem just disappeared.

    All the rdp connection files are setup to use the fully qualified hostnames.

    so that's the somewhat simple scenario, but we actually also have Domain C and D at different locations that also have a trust relationship with Domain A and they also experience the same problem but at totally different times, when Domain B is having the problem domain C and D are not and visa versa. and Domain C and D are Server 2003 for the Domain Controller/DNS server so it's not a server 2008 issue. so it's gotta be some basic problem with conditional forwarding???

    if i can't find a fix for this i need an alternate solution. I am thinking since Domain A only has the 4 servers maybe i can add the hostnames and IP addresses directly in the DNS servers of Domain B,C and D or add it the hosts file on each local computer. or change all rdp connection files to use IP addresses instead of hostnames(about 20 computers per site). unfortunately i am not a DNS wizard and don't fully understand Zones, root hint's and all that other DNS jargon so replies may need to be dumbed down/step by step for me.

    Looking for any suggestions to resolve this irritating random issue.

    Friday, June 10, 2016 3:55 PM

All replies

  • Hi,

    >> i can ping the IP address of the remote desktop server on domain A but cannot ping or nslookup the hostname,

    What result did you get by ping and nslookup when issue occurred?

    Since it shows intermittently,we suggest you could perform a all-day network captuer from client to problem server.Check the capture when issue occurred ,determine where is breaking down.
    Here is the link of Windows network monitor:
    https://www.microsoft.com/en-us/download/details.aspx?id=4865

    >>I am thinking since Domain A only has the 4 servers maybe i can add the hostnames and IP addresses directly in the DNS servers of Domain B,C and D or add it the hosts file on each local computer. or change all rdp connection files to use IP addresses instead of hostnames(about 20 computers per site).

    You could maintain the Domain A zone on your local DNS server,create a new forward lookup zone named DOMAIN A,and add A records for 4 servers in it.

    Hosts file is easier for a small number clients,just add records like below for every clients:

    rds.domainA.com  1.2.3.4

    And change rdp to use IP address is also feasibility.

    ________________________________________
    Best Regards,
    Cartman
    Please remember to mark the replies as answers if they help and unmark them if they provide no help. If you have feedback for TechNet Support, contact tnmff@microsoft.com.

    Monday, June 13, 2016 6:39 AM