Case Study

SCENARIO

ESSENCE OF THE CASE

Following are the essential elements in this case:

• Timeouts are occurring on the LAN.

• Users cannot access resources.

• One side of the network cannot access the other side.

• The original side can access the other side.

You have been hired as a new network engineer to work for ABC Inc., the maker of the world's best widgets. Last week, a new segment was built on to the current LAN and connected via a Windows Server 2003 router. Now, users on the new segment are experiencing timeouts when attempting to access resources on one of the older segments. Nobody is able to get to the other side of the network. Users on the older side of the LAN report no problems at all.

ANALYSIS

As the new network engineer, you need to analyze each problem one at a time and see whether they are all related . This step is important so that you do not waste a lot of time repeating yourself.

As you look at the problems, you realize that you can solve them all within the same device because the router is causing all the problems as a result of it being misconfigured. If you notice timeouts, that means users are complaining of no connectivity, and all the applications that they are trying to open are timing out because the servers they connect to cannot be reached. Because the resources are on the other segment across the router, you know the router is at fault if no one can pass traffic over it.

Next, you see that because one side of the network can access the other side, but not the other way around, this problem may be indicative of a missing route. As a sharp network engineer, you quickly open a command prompt on the server and type route print . This shows you that a route is missing its routing table. You figure out that a dynamic routing protocol is not being used, only static routes, and one route is missing. After adding the missing route, you can discover that the timeout problems have disappeared, and the remote hosts can now access their resources.