General discussion

  • Creator
  • #2148196

    Windows Small Business Server with Router!


    by zmrehman ·

    I have a BT 2Wire Router with one Small Business Server running 5 clients through a switch. I have setup the network and all clients have been added to the domain, with a networked printer and network drives mapped and everything runs fine there. The server has a static I.P and so do the clients. The Router connects to the network. DHCP has been disabled on the Server. The DNS server address of the clients is the same as the Server.
    The clients run Windows Vista Business. What the problem here I am facing is that the clients have a massively intermittent internet connection. I will get the internet for 5 minutes if that then the connection would drop for another 10-15 minutes, however, times of connection/disconnection are very variable. BT have stated that the router is fine, the network is fine and the firewall settings on the router are fine. There is no firewall on the clients, everything is off in that area. I dont know what to do with this, the connection comes, then goes, comes then goes.
    I believe it may be the DNS? The DNS settings on each client and the server is the server i.p.address. I have not doe anything in DNS Management on the server as well, shall I try the secondary DNS server as the router DNS on all the clients?
    Any ideas? The Server has a perfectly constant and good connection so?
    Any help would be much appreciated.

All Comments

  • Author
    • #2460386

      Your router is the default gateway and it should also be the DNS

      by robo_dev ·

      In reply to Windows Small Business Server with Router!

      Your router IP address should be set as your default gateway and as your DNS server.

      Even though you have a server, in your case it has no role in your client connection to the Internet.

      Therefore if your default gateway (your router) is, the ONLY DNS server listed in your clients (or server) should be that same address (….NOT your server’s IP address.

      Your router acts as a DNS forwarder from the DNS server at your ISP.

      Your clients cannot reliably get DNS unless they have the address of the router as their primary DNS server.

      To test DNS, go to a cmd prompt and type:

      (or whatever website you like).

      If it replies with nothing but errors, then your DNS settings are faulty.

      • #2460366

        Cannot Login though

        by zmrehman ·

        In reply to Your router is the default gateway and it should also be the DNS

        I tried the dns primary settings to the defult gateway
        but i then after rebooting get a message on all the clients after trying to login ‘no domain controller are available for logon”
        But, should I also set the DNS on the server as the default gateway?

        • #2460264

          A fairly simple solution

          by dennis_london ·

          In reply to Cannot Login though

          You could add the DNS and DHCP server roles to your server since everyone is already logging in and getting their connection information from the server. This would eliminate your issue and keep your users NAT’d behind the firewall/router. They are probably NAT’d now but unless you are running a single NIC in your server I don’t see any reason why you wouldn’t let your server do its job.

          NIC 1 can point to your router and be considered external while NIC 2 is directed inside. This is a simple dual-homed firewalling technique that works great for networks less than 25 users/machines. If you’re going to have more connections than I would look at a real gateway/routing solution meant to handle the traffic.

    • #2460125

      What I Would Do

      by bincarnato ·

      In reply to Windows Small Business Server with Router!

      If you want to keep DHCP at the router then I would have the SBS Server as the Primary DNS and the router as a secondary DNS. You are running SBS so I would assume that you are running Active Directory. That being said, Active Directory and DNS go hand in hand. I would re-enable DNS Server on your SBS and then on your SBS server I would right click on your forward lookup zone and then add your ISP’s DNS servers to the forwarders tab. On your server I would have itself as the primary DNS and the ISP’s DNS servers as secondary, for redundancy.

      As a personal preference, I would move DHCP server to the SBS because there is SO much more you can do with it, (time server, WINS, reservations, etc.) but that is purely a preference.

      I would also try and figure out where the internet connection is breaking. When you know the connection is down I would from a command prompt see how far out you can ping.

      From command prompt:
      ping “router internal IP address”
      Check for replies

      ping “ISP DNS IP address”
      Check for replies

      ping “ISP Gateway IP Address”
      Check for replies

      check for replies
      If you get replies from all but when you ping Google and get “unable to resolve host name” or what ever the error is, then it is a DNS issue. I would run a lookup on Google’s IP address when the internet is “working” then you can try to ping that address as well.

      From command prompt: nslookup

      Note the IP address

      When the internet “drops”, open internet explorer and put “http://(IP Address from nslookup earlier” and see if the page comes up.

Viewing 1 reply thread