Introduction

This

Beginning the configuration

Starting with a fresh router lets begin by setting up our local inside interface. This is going to be FastEthernet0. We are going to assign this interface an address of 192.168.128.1. To do this from the routers command prompt enter the following commands:

Firstly if you are not already in configuration mode enter it by the following command:


interface FastEthernet0
description Inside Interface
ip address 192.168.128.1 255.255.255.0
duplex auto
speed auto

Introduction

As you probably are aware the Cisco ASA is the successor to the Cisco PIX. If you are like me you are used to using the "debug packet" command for doing a lot of your connectivity trouble shooting. With the ASA you can use a command which is similar (albeit improved) version of the debug packet called "capture". As well as the new capture command the Cisco ASA also has a graphic logging tool known as the Cisco ASA ASDM logging tool.

Cisco IOS "do" command

When you are configuring a cisco router you are in config mode. Often you need to check what you are doing and that means leaving config mode and entering into priviledged mode. This can be a pain in the neck. Users of Cisco Pix and Cisco ASAs have don't have to do this. Pix and ASA users can run commands like show run when in config mode.

Well there is some good news - if you run IOS 12(8) or later you will find you have a new command called "do".

When you are setting a site to site VPN between two Cisco ASA IPSEC peers you may find it useful to turn on the debug command for phase 1 tunnel initiation. Phase 1 uses a key exchange protocol called ISAKMP. With this in mind I often turn on the Crypto ISAKMP debugging on the command line to provide me with useful feedback when setting up a vpn. This is done using the following command:

Please note the trailing 8 is the level of debugging information you want sent to your console. This is configurable between 1-255.

Introduction

The Cisco 837 ADSL / Broadband router like most Cisco routers can have it's software( firmware ) upgraded. Generally this isn't a difficult process but it is a bit fiddly if you haven't done it before. This guide will walk you through this process.

Requirements

Cisco 837 router and Cisco console cable

Fairly obvious really, this is the router you wish to upgrade and the cisco serial cable used to configure the router.

Cisco 837 Firmware image

Command to set boot system switch all flash failed

If you are using upgrading the Cisco IOS version on the switch stack manually you normally set the boot variable on the switches to use the new IOS file you have uploaded. If your switch stack has more than one member (it isn't really a stack if it doesn't) you must copy the ios to the flash of each member switch.

Otherwise when you issue the

command

When recovering a Cisco 3750 a flash error can occur

If you ever have to recover a Cisco 3750 switch or switch stack password there are some good instructions on the cisco web site on how to do this. However, part of the process involves accessing file(s) on the flash memory of the switch. Occasionally you might run into a problem when attempting to access the flash memory. The switch may report "unable to stat flash:/: invalid" argument.

For example when you type

you may receive and error which says

If you need to backup your network device's (you know Cisco, HP etc) running configuration, one of the most common ways to do this is via a TFTP server. There are various tftp solutions out there and this guide covers setting up a centos box on how to become a tftp server. There a few guides out there already but this one covers Centos 5 Linux specifically.

Step 1.
You need to install the tftp-server service and the xinetd service software using yum.
The xinetd service is required as this controls the tftp server daemon.

Using a client VPN IPSEC for remote access is a very good and is a widely used solution. However, it does require two things to work.

1. A VPN client

2. The correct IP protocol access.