Cisco 3550 Switch Ios

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Download the latest IOS image for your cisco website. Go to cisco.com - IOS Software - Select your Siwtch (for example: Cisco Catalyst Switch 3750G-24T) - Click on “Download IP BASE” - Select the latest version that you want to download (for example: 12-2.55.SE1). While you are on this download page, copy/paste the MD5 given to your system. Switch: I tried this twice, and both times didn't work. I then downloaded an earlier IOS version, and tried with that file:'c3550-i5q3l2-mz.121-22.EA1.bin' Same problem. Here's my most recent attempt.

Unfortunately there is no easy way to recover a corrupt or deleted IOS image on a fixed configuration Cisco Catalyst switch. You must use xModem which commonly takes 2+ hours. This lab will discuss and demonstrate the IOS recovery procedure for fixed configuration Catalyst series switches using xModem.

Real World Application

Recovering the Cisco IOS image on a Cisco switch is one of those tasks that is nice to know and not need it then need it and not know it. In the field you may find yourself faced with a Cisco switch that cannot boot up or crashes when booting up due to a possible IOS Image corruption.

Lab Prerequisites

  • This lab will require a REAL switch as this lab cannot be emulated using GNS3.
  • The Cisco IOS on the switch must be corrupt or missing to perform this lab, to emulate this error you can erase the flash memory to practice this lab.
  • An active console session to the device is REQUIRED.
  • You’ll need to use either HyperTerminal or SecureCRT as Putty does not support xModem.

Lab Objectives

Document Display | HPE Support Center

  • Boot the switch into SWITCH ROM mode.
  • Initialize the flash file system.
  • OPTIONAL – Format the flash file system if needed. (This will remove your startup configuration)
  • Set the baud rate to 115200 to increase xmodem transfer speed and decrease time required to restore the IOS Image.
  • Copy the Cisco IOS Image via xModem to Flash:
  • Set the boot parameter to the new image name located in Flash:
  • Unset the baud so that it defaults back to 9600.
  • Boot the switch and verify that the switch boots properly.

Lab Instruction

Cisco 3650 Switch Ios Update Procedures

Switch

Recovering the Cisco IOS Image on a fix configuration Cisco Catalyst Series Switch is quite a bit different and more of an “old school” way of doing an IOS image recovery. Unfortunately fixed configuration switches require the use of xModem to restore a corrupt or missing IOS images unlike the Cisco 4500 and Cisco 6500 Series supervisor engines which use compact flash cards

Step 1. Boot your switch into switch ROM mode. This typically involves holding down the STAT button on the front of the switch when plugging in the power. You can check out the required procedure by clicking HERE!

Once you’ve booted your switch into Switch ROM mode you’ll be see the following dispatch;

Step 2. Once you’ve booted into Switch ROM mode you’ll need to initialize the flash file system by executing the flash_init command as shown below;

Step 3 – OPTIONAL – If your image is corrupted you can format your flash file system by executing the format flash: command as shown below however this will delete your start-up configuration!!!

Step 4. To speed up the xModem file transfer speed you’ll need to set the console line BAUD rate to 115200 by executing the set BAUD 115200. If you do this you’ll need to disconnect your console session and change the serial line speed from 9600 to 115200. However if you do not set the BAUD to 115200 your file transfer can take up to 3 hours.

Step 5. Once setting the BAUD rate and reconnecting to the console line of your Cisco switch you’re ready to copy the IOS image via xModem to the switch’s flash memory by executing the copy xmodem: flash:filename.bin and starting the xModem file transfer from the terminal emulator client as shown below;

Step 6. Once the IOS image is copied into flash you’ll need to update the BOOT parameter by executing the set BOOT flash:filename.bin command as shown below;

Cisco 3550 Switch Ios

Step 7. Once the boot parameter has been set you can now set the BAUD rate back to the default 9600bps by executing the command unset BAUD. Note that when doing this you’ll need to disconnect your current console connection and change the baud speed on your terminal emulator from 115200 back to 9600.

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Step 8 is the last step which is to boot the switch and verify that the switch successfully boots the IOS image placed into flash from xMODEM. Execute the boot command to load the IOS image specified in the boot parameter as shown below;