ML
    • Recent
    • Categories
    • Tags
    • Popular
    • Users
    • Groups
    • Register
    • Login

    DNS Across VLANs

    IT Discussion
    dns vlan networking
    5
    9
    2.3k
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • pchiodoP
      pchiodo
      last edited by scottalanmiller

      We have 5 VLANs, but for simplification, I am going to limit this to 2 VLANs for this particular issue.

      VLAN 1 - Server VLAN 192.168.1.x - 255.255.252.0
      VLAN 2 - Client VLAN 172.16.2.x - 255.255.252.0

      Server - TestServer1 - IP - 192.168.1.88 static

      Client - TestClient1 - IP - 172.16.2.110 DHCP

      From the server I can ping the client by either hostname or IP. If I use -a with the IP it returns the hostname.

      From the client, I can ping the server or another client by hostname or IP. If I use -a with the IP the hostnames are returned.

      If I use NSLOOKUP from the server to the client it fails with the following error:

      [DNS Server].[domain] can't find 172.16.2.110: Non-existent domain

      If I use NSLOOKUP from the client to the server, it works fine

      If I use NSLOOKUP from one client to another client, it fails with the same error.

      I thought this has to be a reverse lookup issue, but I can't seem to sort it out. Any help would be appreciated.

      JaredBuschJ 1 Reply Last reply Reply Quote 1
      • JaredBuschJ
        JaredBusch @pchiodo
        last edited by

        @pchiodo said:

        We have 5 VLANs, but for simplification, I am going to limit this to 2 VLANs for this particular issue.

        VLAN 1 - Server VLAN 192.168.1.x - 255.255.252.0
        VLAN 2 - Client VLAN 172.16.2.x - 255.255.252.0

        Server - TestServer1 - IP - 192.168.1.88 static

        Client - TestClient1 - IP - 172.16.2.110 DHCP

        From the server I can ping the client by either hostname or IP. If I use -a with the IP it returns the hostname.

        From the client, I can ping the server or another client by hostname or IP. If I use -a with the IP the hostnames are returned.

        If I use NSLOOKUP from the server to the client it fails with the following error:

        [DNS Server].[domain] can't find 172.16.2.110: Non-existent domain

        If I use NSLOOKUP from the client to the server, it works fine

        If I use NSLOOKUP from one client to another client, it fails with the same error.

        I thought this has to be a reverse lookup issue, but I can't seem to sort it out. Any help would be appreciated.

        Just to clarify where the problem is here. It looks like ping by name and IP all return the right information?

        So only NSLOOKUP is failing?

        pchiodoP 1 Reply Last reply Reply Quote 0
        • iroalI
          iroal
          last edited by

          What are the DNS configuration in 172.16.2.x ?

          1 Reply Last reply Reply Quote 0
          • pchiodoP
            pchiodo @JaredBusch
            last edited by

            @JaredBusch Correct - only NSLOOKUP fails, but only from server to client, and client to client. It works fine client to server.

            JaredBuschJ 1 Reply Last reply Reply Quote 0
            • JaredBuschJ
              JaredBusch @pchiodo
              last edited by

              @pchiodo said:

              @JaredBusch Correct - only NSLOOKUP fails, but only from server to client, and client to client. It works fine client to server.

              That one stumps me. You can ping form the server but not nslookup. No clue.

              1 Reply Last reply Reply Quote 0
              • scottalanmillerS
                scottalanmiller
                last edited by

                What's the exact syntax of the failing nslookup command?

                pchiodoP 1 Reply Last reply Reply Quote 0
                • pchiodoP
                  pchiodo
                  last edited by pchiodo

                  I think we got it sorted out - We added a reverse lookup zone for the subnet 172 as follows:

                  172..in-addr.arpa

                  As an Active Directory-Integrated Primary, and allowed it time to update the PTRs, and now it is working correctly.

                  Thanks

                  1 Reply Last reply Reply Quote 0
                  • pchiodoP
                    pchiodo @scottalanmiller
                    last edited by

                    @scottalanmiller We were attempting "NSLOOKUP 172.16.2.110" and receiving the stated error. As per my previous response, I think we got it fixed by adding the reverse lookup zone, and allowing it time to propagate.

                    DashrenderD 1 Reply Last reply Reply Quote 0
                    • DashrenderD
                      Dashrender @pchiodo
                      last edited by

                      @pchiodo said:

                      @scottalanmiller We were attempting "NSLOOKUP 172.16.2.110" and receiving the stated error. As per my previous response, I think we got it fixed by adding the reverse lookup zone, and allowing it time to propagate.

                      Interesting.. for some reason I thought you were trying to NSLOOKUP using the client as a DNS server, which of course would fail.

                      1 Reply Last reply Reply Quote 0
                      • 1 / 1
                      • First post
                        Last post