The document discusses managing Cisco IOS software. It covers the router boot sequence, locating and loading the IOS, configuration register values, IOS software components, managing configuration files using TFTP and copy/paste, and loading IOS images using TFTP and Xmodem. Environmental variables are used to download an IOS image from ROMmon mode using TFTP. The file system can be verified using show commands.

1. MANAGING CISCO IOS SOFTWARE TS, PHẠM VĂN TÍNH PART9

2. Objective Identify the stages of the router boot sequence Determine how a Cisco device locates and loads the Cisco IOS Use the boot system command Identify the configuration register values Briefly describe the files used by the Cisco IOS and their functions List the locations on the router of the different file types Briefly describe the parts of the IOS name Save and restore configuration files using TFTP and copy-and-paste Load an IOS image using TFTP Load an IOS image using XModem Verify the file system using show commands

3. Stages of the router power-on boot sequence the startup routines must do the following: Test the router hardware. Find and load the Cisco IOS software. Find and apply configuration statements, including protocol functions and interface addresses.

4. Locating IOS Software

5. Configuration register The order in which the router looks for system bootstrap information depends on the boot field setting in the configuration register. The default configuration register setting can be changed with the global configuration mode command config-register . Use a hexadecimal number as the argument for this command

6. Software Components In Memory

7. Fields in the IOS Name

8. Managing configuration files using copy and paste to capture the configuration using the text displayed on the HyperTerminal screen to a text file: Select Transfer Select Capture Text Specify the name for the text file to capture the configuration Select Start to start capturing text Display the configuration to the screen by entering show running-config Press the space bar when each "-More -" prompt appears When the complete configuration has been displayed, stop the capture by: Select Transfer Select Capture Text Select Stop

9. Managing configuration files using copy and paste Restore the configuration using the text file from the HyperTerminal software: Enter router global configuration mode. From HyperTerminal, click on Transfer > Send Text File . Select the name of the file for the saved backup configuration. The lines of the file will be entered into the router as if they were being typed. Observe any errors. After the configuration is entered, press Ctrl-Z key to exit global configuration mode. Restore the startup configuration with copy running-config startup-config .

10. Managing IOS images using TFTP

11. Managing IOS images using Xmodem If the IOS image in flash has been erased or corrupted, the IOS may need to be restored from the ROM monitor mode (ROMmon). To restore the IOS through the console, the local PC needs to have a copy of the IOS file to restore and a terminal emulation program such as HyperTerminal. The IOS can be restored using the default console speed of 9600 bps . The baud rate can be changed to 115200 bps . The console speed can be changed from ROMmon mode using the confreg command

12. Managing IOS images using Xmodem xmodem -c image_file_name For example, to restore an IOS image file with the name “c2600-is-mz.122-10a.bin”: xmodem -c c2600-is-mz.122-10a.bin In HyperTerminal, select Transfer > Send File . Then in the Send File popup specify the image name/location , select Xmodem as the protocol, and start the transfer Before restarting the router , the console speed needs to be set back to 9600 and the config register back to 0x2102 by command config-register 0x2102 at the privileged EXEC prompt

13. Environment variables Downloading the image using TFTP from ROMmon is the fastest way to restore an IOS image to the router. This is done by setting environmental variables and then using the tftpdnld command. The ROMmon TFTP transfer works only on the first LAN port so a simple set of IP parameters are set for this interface. Syntax : VARIABLE_NAME = value Note: All variable names are case sensitive To check the ROMmon environment variables, the set command can be used

14. List of Environment variables IP_ADDRESS – The IP address on the LAN interface IP_SUBNET_MASK – The subnet mask for the LAN interface DEFAULT_GATEWAY – The default gateway for the LAN interface TFTP_SERVER – The IP address of the TFTP server TFTP_FILE – The IOS filename on the server

15. File system verification show version show flash