A detailed analysis of Cisco router configuration

Users using Cisco routing, many of them do not pay much attention to doing Cisco router configuration work, in fact this is a very important part, especially for our network security. There are several ways to do Cisco router configuration. The configuration can be done by the TFTP server over the network, through the menu interface provided at startup, and by the menu interface provided by running the Setup command, or by a configuration saved to memory. This tutorial does not cover these methods, it only covers configurations made by the iOS command line interface.

One is speed. Once you've taken the time to understand command-line commands, you can do a lot more quickly than by using a menu. Basically, this is true relative to all the command lines in the menu. It is particularly useful for understanding the command-line interface of Cisco IOS, and Cisco IOS is the standard across all Cisco routers. Second, you can configure a single interface without disrupting services on other interfaces. By definition, the Cisco router configuration has multiple interfaces. For example, in the Cisco 7200 series Router, routers have multiple ports, each with several hot swappable modules. The ability to configure these modules individually via the command line is a valuable technique. At the beginning of

, you might configure your router via a terminal. If the router is already configured and at least one port has been configured with an IP address and it is physically connected to the network, you may be able to telnet to the router and configure it over the network. If the router has not been configured, you will have to connect it directly with a terminal and a serial cable. For any Windows host, you can easily connect to a router using HyperTerminal (HyperTerminal). Plug the serial cable into the serial port (COM) on the PC, and the other end to the console port on the Cisco router. Start HyperTerminal, tell it what COM port you are using and click OK. Set the connection rate to 9600 baud and click OK. If the router is not powered on, start it. If you want to be configured by a Linux host for Cisco router, run Seyon or minicom. At least one of them, perhaps two of them, is in your Linux-wigs piece.

If you have just opened the router, it will ask you after booting, and if you want to start the initial configuration, answer No. If you answer yes, it will bring you into the menu interface. So answer No. The Cisco iOS command line interface is organized around the concept of schema (Modes). In the Cisco router configuration, you have to enter and exit between several different modes, and the mode determines the command used. Each pattern has a complete set of commands that can be used for that pattern, and some of theseThe command can only be used for this mode. In any mode, entering a question mark displays a list of commands for that pattern.

Enter EXEC mode The first time you connect to the router and provide a password (if necessary). In the first mode, you can run commands from the command line. Here, you can use unprivileged commands such as Ping, Telnet, and rlogin. You can also use a set of SHOW commands to get information about the system. In unprivileged mode, you can use a command such as show version to display the version number of the iOS that the router is running on. Enter show

Cisco router configuration must enter privileged mode. You can do this by using the Enable command. Privileged mode is usually password protected unless the Cisco router is configured properly. You have the option of password-protected privilege mode, but strongly recommend that you choose a password-protected privileged mode. After you run the command to enable and provide the password, you will enter the privileged mode. To help users see the pattern, the command line prompts change each time they enter a different mode. 3lian.com

This may not be the best way to handle this, if there are only two modes. In fact, there are a large number of models, such characteristics may be absolutely necessary. Always pay close attention to tips at all times.　There are many sub modes in privileged mode. In this article, I'm not going to follow the Cisco terminology of this pattern hierarchy. Frankly speaking, I think my explanation is clearer. Cisco describes two modes, the unprivileged mode and the privileged mode, and then the command hierarchy used in privileged mode. My reason is very clear, to figure out if you only consider the many sub modes of privileged mode. Privileged mode, and I call it the parent mode. Once you enter the privileged mode (parent mode), the prompt ends with the pound sign (#). Only after entering the privileged mode can you enter a large number of patterns. All child modes of

still end with the # symbol, which is included in privileged mode. Most patterns have their own child mode. Once you enter privileged mode, you have access to all configuration information. The configuration information can optionally be provided by iOS or provided directly by the parent mode or provided by one of the child modes, if you just turn on the router, it will be completely unassigned. If it has already been configured, you may want to view its current configuration. Even if it has not previously been configured, you should familiarize yourself with the use of the show command before starting the Cisco router configuration. Enable access to privileged mode by running the command, and then run several Show commands to view the information they display.　Remember, command show? All show commands that are available for the current mode are displayed.