This article has been written to help those who are practicing with Cisco devices and will describe how to recover the IOS image in Flash memory on a Cisco 2950 Switch

The IOS image file is stored in Flash memory on a 2950 series Switch. On booting the IOS image file is decompressed and copied into RAM, making available the command prompt for configuration

When the IOS image is corrupted or the boot variable is incorrectly set the Switch will normally no longer boot and will provide the following message:

Error loading “c2950-i6q4l2-mz.121-9.EA1.bin”

Interrupt within 5 seconds to abort boot process

Boot process failed…

Resulting in a prompt of: Switch:

At this prompt type: flash_init This will initialise flash

NOTE: Most not all commands are case sensitive

Then type: dir flash: This will show the contents of flash memory.

An example is shown below

Directory of flash:/

3 -rwx 41 Mar 01 1993 00:05:42 env_vars

4 -rwx 108 Mar 01 1993 00:06:05 info

5 -rwx 1644 Mar 01 1993 00:34:51 config.text

6 -rwx 108 Mar 01 1993 00:06:21 info.ver

In this example there is no .bin image file, therefore an Xmodem file transfer MUST be used to reinstate it.

However if the file exists the boot statement may not have been set correctly.

Try typing: boot flash:c2950-i6q4l2-mz.121-9.EA1.bin (assuming c2950-i6q4l2-mz.121-9.EA1.bin is the name of the .bin image file)

If the boot statement is the problem the Switch will now boot in to the User Exec mode prompt , if this command fails then the Xmodem file transfer is the only alternative as the existing image is probably corrupt

The existing image can be deleted using the command:

delete flash:c2950-i6q4l2-mz.121-9.EA1.bin

To use an Xmodem file transfer a backup copy of the image file must be available

Type: copy xmodem: flash: c2950-i6q4l2-mz.121-9.EA1.bin

This will result in the following response

Begin the Xmodem or Xmodem-1K transfer now ….

CCC

From the HyperTerminal window select Transfer > Send File

In the send file window click on the “Browse” button and select the path to your backup image file, now use the Protocol drop down box and select “Xmodem”. Then click on Send

The Xmodem transfer will start, this will take some time depending on the image file size, the following will be displayed

CCCCCCC…..

When complete the following message is displayed:

File “xmodem” successfully copied to “flash:c2950-i6q4l2-mz.121-9.EA1.bin”

Now type: boot system flash:c2950-i6q4l2-mz.121-9.EA1.bin

The Switch will reboot and take you to the User Exec prompt: Switch>

Enter Privileg Exec mode by tuping: ENABLE The prompt will change to: Switch#

From privilege Exec verify that the image exists by typing the following commands:

Show version This will display the image file name

Dir flash:c2950-i6q4l2-mz.121-9.EA1.bin This will display the image file in flash

Show boot To show the boot system settings

NOTE: If a boot statement does not exist enter Global Configuration mode and type:

boot system flash:c2950-i6q4l2-mz.121-9.EA1.bin

When the show boot command is then retyped in privilege exec the file will be displayed in the path-list

You can now reboot and use the switch.