Why Network Troubleshooting Will Change Your Life.
OK maybe it won’t change your life but it will demand a considerable amount of your time until you get it running properly.
Windows domain best practice is to use the domain server/s for DNS & DHCP. While these features are typically enabled on routers they cause a lot of grief on a Windows domain. Routers may know where the main DNS servers are on the Internet but they have no idea where your network servers are.
Consequently, the router will start looking for your server on the Internet 1st and then start interrogating your network. That yields an unnecessary lag time for searches for machines that are on your network.
This article primarily addresses a single server domain but the principles are similar for larger environments.
DNS – Domain Name System
If you are experiencing a lag time trying to find or connect to your server using a Fully Qualified Domain Name (FQDN) then your network may be misconfigured. Best practice is to have your DNS server reference itself and all the other PCs get their information from the local DNS server.
Since we are mainly focused on single-server domains then DNS will be on the domain controller.
domain – example.com
LAN – 192.168.0.xxx
gateway – 192.168.0.1
server.example.com – 192.168.0.2
DNS – 192.168.0.2
Once we setup the server static IP to use itself for DNS then the server won’t have any problems finding machines on the local network.
DHCP – Dynamic Host Configuration Protocol
The easy way to setup PCs on your network is to use DHCP. This tells the device where your DNS server, gateway are in addition to assigning an IP address from a pool. For a home setup it’s easy enough to let the Internet router take care of these responsibilities. For a domain, however, we want our server to handle DNS and DHCP too.
We will want to disable DNS & DHCP on the router (gateway) and add the roles to the server.
The DHCP server will issue is from our address pool and set the client PCs DNS to use the server ip for DNS.
Static ip Addresses
Machines like the server need static ips so that we always know what address it has. If you allow devices to use DHCP addresses then they may or may not get the same ip every time which can lead to more network problems for devices you connect to via an ip.
In our example, the server is at 192.168.0.2 on our Local Area Network (LAN). That means we had to assign an ip outside of the DHCP pool, subnet mask, gateway and DNS server (itself).
Best practice is to use a static ip for your server so we don’t end up with some sort of conflict. If other devices use static ips, then you will need to adjust the DNS on those devices if they are not set to your server.
Network troubleshooting may not change your life but it will definitely improve the quality of time you spend on your attached computers.