Chap 7 IOS Images Andres, Wen-Yuan Liao Department of Computer Science and Engineer ing De Lin Institute of Technology [email protected] http://www.cse.dlit.edu.tw/~andres
Jan 04, 2016
Chap 7IOS Images
Andres, Wen-Yuan Liao
Department of Computer Science and Engineering
De Lin Institute of Technology
http://www.cse.dlit.edu.tw/~andres
Overview
Cisco IOS software source optionsLoad IOS software onto the routerMaintain backup filesUpgrade IOS software
The functions of the conf. register
The Basics of IOS Versions
Locating the Cisco IOS software
Configuration register values
The show version command
Locating the Cisco IOS software
The default source depends on the hardware platform
The router looks to the boot system commands saved in NVRAM
NVRAMConfiguration register: Boot fieldROM moniter / ROM / Boot system
commandRouter#config-register
Boot system commandFlash/TFTP/ROMRouter(config)#boot system
Boot system
Global configuration-mode boot system commands to enter fallback sources for the router to use in sequence
Configuration register values
Configuration register:boot fieldDetermine the order in which the rout
er looks for system bootstrap information
Router#config-registerChange the default configuration regi
ster setting
The configuration register is a 16-bit register in NVRAM
The lowest 4 bits bits 3,2,1,0: the boot field
show version: verify the config-register command
Configuration register values
(default)
The show version command
Displays information about the Cisco IOS software version (system image)
The configuration register and the boot field setting
Bootstrap Options in Software
Boot system commands
Preparing for the use of TFTP
The show flash command
Preparing for the use of TFTP
A TFTP server will allow image and conf. uploads and downloads over the networkAnother router or host system
The show flash command
Verify that you have sufficient memory on your system for the Cisco IOS software
Always backup your current IOS before upgrading to a newer version
IOS Naming and Software Image Backup
Cisco's IOS naming conventions
The copy flash tftp command
The copy tftp flash command
How to load a software image backup
Cisco's IOS naming conventions
These images accommodate the various platforms, available memory resources, and feature set needs customers have for their network devices
The copy flash tftp command show flash command to learn the name of the system image file (xk09140z)copy flash tftp command to copy the system image to a TFTP server
The copy tftp flash command
copy tftp flashDownload the new image from the TFTP server
Flash memory for more than a single Cisco IOS image
Exclamation point (!) : successfully transferredVs: successful checksum verification
Summary
Configuration commands in NVRAM
The show version command
IOS: Flash/TFTP server/ROM
show flash
Naming convention
copy flash tftp/copy tftp flash