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Cisco 3750 - IOS change

Tencha asked
The factory version of the switch was not ideal, so a contractor upgrade the switch to a new version. I went in the switch,

(config)#boot system flash:/c3750-ipservicesk9-mz.SE1.bin
# reload

Initializing flashfs...

flashfs[1]: 935 files, 14 directories
flashfs[1]: 0 orphaned files, 0 orphaned directories
flashfs[1]: Total bytes: 32514048
flashfs[1]: Bytes used: 30834176
flashfs[1]: Bytes available: 1679872
flashfs[1]: flashfs fsck took 17 seconds.
flashfs[1]: Initialization complete....done Initializing flashfs.

Checking for Bootloader upgrade.. not needed
POST: CPU MIC register Tests : Begin
POST: CPU MIC register Tests : End, Status Passed

POST: PortASIC Memory Tests : Begin
POST: PortASIC Memory Tests : End, Status Passed

POST: CPU MIC interface Loopback Tests : Begin
POST: CPU MIC interface Loopback Tests : End, Status Passed

POST: PortASIC RingLoopback Tests : Begin
POST: PortASIC RingLoopback Tests : End, Status Passed

front_end/ (directory)
extracting front_end/fe_type_1 (34760 bytes)
extracting front_end/fe_type_2 (78400 bytes)
extracting front_end/front_end_ucode_info (86 bytes)
extracting ucode_info (76 bytes)

I''ve been waiting for about 15mins from "extracting"... is this normal or is this an error?
I'm getting worried....
Watch Question

Certainly not typical. Did it ever return an error or?


NO it did not, it finally went through. But it appears that it did not help any, I still have the same configuration, no how to blow it out of the water but keep the same version?
Istvan KalmarHead of IT Security Division
Top Expert 2010


It seems the image maybe corrupted, so you need to upgrade it, there is two way:


tftpdnld is faster, but not all devisec supported it!:(

Best regards,
An alternative is you could boot to rommon mode, rename the config file and then  boot to a blank configuration which will load the standard IOS if you still have it in flash then copy the sved config into the running config and delete the

boot system  flash:/c3750-ipservicesk9-mz.SE1.bin

command form your config. You would then be back to where you were before the attempted upgrade.

To get to rommon hold the mode button whilst powering up the switch until the STAT LED goes out, and you should get the switch: prompt on the console. then issue the following commands


Do a dir of the flash to list the contents.

switch:dir flash:

Now rename the config file and boot the switch

switch:rename flash:config.text flash:config.old

This should boot the switch with a blank configuration but from the default IOS. Ignore the initial configuration prompts to get back to the switch prompt, then issue these commands to restore your config.

switch> enable
switch# copy flash:config.old running-config

This should resote your old config prior to the point where it tried to load the new IOS form flash. Dont forget to write your config or you will go back to a blank config if you reboot the switch.


It worked now I can configure the switch.