Recover ios on not so-old Cisco Switch

I messed up a 3-stack 3750 switch today when testing spanning-tree between Cisco and HP. Somehow I corrupted ios on one switch in the stack. So it was long day to recover it. The process also applies to recover deleted/lost ios.

1. Download the ios for 3750 switch from Cisco

2. Download Tera Term (skip this to use Hyperterminal if you are still running XP)

3. Connect to switch use console cable with Tera Term

4. The “bad” switch will boot up to prompt switch:

5. From switch:, type in flash_init and you should have following output: Initializing Flash…

6. Then do dir flash: to make sure you can actually see the files in flash and also there is enough space left for your new ios.

7. Run set BAUD 115200 to have a faster transfer speed as we will use modem to upload the ios.

8. Exit tera term and re-open tera term.

9. Set the baud rate to 115200 in tera term for COM port to connect

10. Type in copy xmodem: flash:c3750-ipbasek9-mz.122-55.SE7.bin

11. Then inside Tera Term under File menu to Transfer to xmodem to send file.

12. Once the new ios is on switch, type in boot flash:c3750-ipbasek9-mz.122-55.SE7.bin

13. Now you should be able to do what you normally do with Cisco switch

Cisco official guide is here.

If you really want to use HyperTerminal on Windows 7, then try to copy following 2 files from a windows XP machine over to Windows 7. If you can not find a XP, then download from here.

C:\Program Files\Windows NT\hypertrm.exe



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