星期日, 8月 02, 2009

Isolating problems occurring at layers 1 and 2

1. If you encounter a line protocol down message on a router interface, what is is an indication of?

The IGRP neighbour agencies are operational on that interface
The problem lies with another router
There is a problem with the interface at the data-link layer that prevents it from functioning properly
There is a problem with the interface at the physical layer that prevents it from functioning properly



2. A group of users reports that its connection to the network has gone down due to a problem in either the physical or data-link layer. You check the operational status, errors, and configuration of the affected interfaces. You still have not found the cause of the problem.
Which guideline for isolating a problem at the physical and data-link layers have you omitted?

Checking cable configuration
Disabling Spanning Tree
Verifying the IP address of the default gateway
Viewing TCP information on a host




3. While testing your FastEthernet 0/1 interface, you have noticed some packet loss. What command should you use to isolate this problem?

debug frame-relay lmi
show interface FastEthernet 0/1
show ip interface brief
show running-config interface




4. While working on the FastEthernet 0/1 interface, you realise that it is performing poorly under load. After running a diagnostic, you discover that there are a high number of late collisions recorded. What is this an indication of?

That the duplex configuration may be mismatched
That the interface has lost its connection to the device on the other end of the Ethernet cable
That the interface has restarted itself after an error condition
That there is a problem with the interface at the data-link layer