Basic configurations of Cisco Routers

With the rapid development of the IT industry, Cisco routers are widely used in all walks of life. This article will start with the basic configuration and briefly introduce the configuration method of Cisco routers.
　　
1. Configure the Ethernet port # conf t
　　
Configure the router from the terminal (Cisco commands can be abbreviated as "conf t", as long as they are not repeated with other commands. For example, configure terminal can be written as "conf t ).
　　
# Int e0
Specify the E0 port.
# Ip addr ABCD XXXX
ABCD is the ethernet address, and XXXX is the subnet mask.
# Ip addr abcd xxxx secondary
The E0 port supports multiple address types at the same time, as long as each address type is not in the same network segment.
# No shutdown
Activate E0 port.
# Exit
　　
2. Configure the SERIAL port (SERIAL)
　　
1. X.25 Configuration
# Conf t
# Int S0
# Ip addr ABCD XXXX
# Ip addr abcd xxxx secondary
The S0 port also supports multiple address types.
# Encap X25
Encapsulate the X.25 protocol.
# X25 addr ABCD
ABCD is the X.25 port address of S0, which is provided by the Telecommunications Department.
# X25 map ip abcd xxxx br
Ing X.25 address, ABCD is the IP address of the Peer router (such as S0), XXXX is the peer Router
(Such as S0) X.25 port address.
# X25 htc X
The maximum number of two-way channels X ranges from 1 ~ 4095. It must be configured according to the number actually provided by the post office.
# X25 nvc X
Configure the number of permanent virtual circuits. X cannot exceed the value actually provided by the post office. Otherwise, normal data transmission will be affected.
# No shutdown
# Exit
2. Frame Relay Configuration
# Conf t
# Int s0
# Ip addr ABCD XXXX
# Encap frante_relay
# No nrzi_encoding
NRZI = NO.
# Frame_relay lmi_type q933a
　　
LMS uses the Q933A standard. There are three types of LMS (Local management Interface): ANSI T1.617, CCITT Q933A, and Cisco-specific standards.
# Frame-relay intf-typ ABC
　　
ABC is a frame relay device type. They are DTE devices, DCE switches, and NNI (Network Contact Interface) support devices.
# Frame_relay interface_dlci 110 br
　　
Configure the DLCI (data link connection identifier ).
# Frame-relay map ip abcd xxxx broadcast
　　
Creates a frame relay ing. ABCD is the IP address of the other party, XXXX is the local DLCI number, and broadcast allows the broadcast to forward or update the route.
　　
# No shutdown
# Exit
3. Configure the Frame Relay subinterface
# Conf t
# Int s0.1 point-to-point
Corresponding to S0 sub-interface 1, point-to-point mode.
# Ip addr ABCD XXXX
ABCD is the IP address of sub-Port 1, and XXXX is the subnet mask.
# Frame-relay interface-dlci 100 br
4. Configure dial-up backup
(1) configure the backup master Port
# Conf t
# Int s0
S0 is the main port.
# Backup int asy 1
The A1 port is the backup port.
# Backup delay 0 1
The delay is 1 second.
(2) Configure virtual Interfaces
# Conf t
# Ip addr ABCD XXXX
ABCD is the IP address of the virtual interface, and XXXX is the subnet mask.
# Encap ppp
# Dialer in-band
Activate the call-on-demand function.
# Dialer idle-timeout 7200
# Dialer map ip ABCD modem-script call
Broadcast 1234567 br
Maps the corresponding dialing port. ABCD is the IP address of the Peer dialing port, and 1234567 is the corresponding phone number.
# Dialer_group 1
Defines the dial-up group members.
(3) configure the firewall
# Dialer_list 1 pro ip permit
Allow the IP protocol to pass.
(4) configure the connection password
# User name ABCD pass XXXX
ABCD is the host name of the other party, and XXXX is the connection password.
(5) configure the dialing string
# Conf t
# Chat-script call "abort busy abort error" atdt 1234567 TIMEOUT 45 "CONNECT"
1234567 is the recipient's phone number.
(6) configure the dialing connection password
# Conf t
# Username ROU1 pass XXXX
ROU1 is the name of the Peer router, and XXXX is the connection password.
(7) configure the line
# Conft
# Line aux 0
# Modem inout
MODEM bidirectional transmission.
# Modem autoconfigure discovery
Automatically configure MODEM parameters.
# Transport input all
# Speed51200
The sending and receiving rate of MODEM is 51200bps.
# Exit
5. Configure synchronous/asynchronous ports
# Conf t
# Int s2
# Ph asyn
Configure S2 as an asynchronous port.
# Ph sync
Configure S2 as the synchronization port.
　　
3. Configure routes
　　
1. Dynamic Route Configuration
# Conf t
# Router VPN 20
Use the VPN protocol. Common routing protocols include RIP, IGRP, and IS-IS.
# Passive-interface serial0
If S0 is connected to X.25, enter this command.
# Passive-interface serial1
If S1 is connected to X.25, enter this command.
# Network ABCD
ABCD is the local ethernet address.
# Network XXXX
The IP address where XXXX is S0.
# No auto-summary
# Exit
2. Static route Configuration
# Ip router abcd xxxx yyyy 90
ABCD is the ethernet address of the Peer router, XXXX is the subnet mask, and YYYY is the WAN port address of the Peer router.
# Dialer-list 1 protocol ip permail
3. Back up the configuration file to the hard disk
Start the TFTP program on the computer.
# Copy run tftp
Create an empty file on the hard disk and have the read and write permissions.
4. Restore the backup configuration file to the vro
# Copy tftp run
5. Create a backup on the vro
# Copy run start
Article entry: csh responsible editor: csh