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New Member

3750 IOS upgrade

Hi there,

i need help on how to upgrade the IOS image of my 3750 without having to lose any information. It's actually for a client, and i wish to schedule a reload time...the image would be lifted from a tftp server, but i just need to know the steps required to set up the configuration, and also information on whether or not it's going to affect anything. Thanks.


Re: 3750 IOS upgrade


Configurations are stored in the NVRAM whereas the IOS is stored in flash. Upgrading the IOS does not change the configuration.

However, the new IOS may or may not support some features.

for eg. if your old IOS was a cryptographic image and the new one is non cryptographic image, you will lose your SSH configs

HTH, rate if it does


New Member

Re: 3750 IOS upgrade

Thank you so much ma man. I guess i've been studyin so hard, that my basic knowledge is drifting away.

New Member

Re: 3750 IOS upgrade

If you have these in a stack configuration, and you only have one management IP address, you can upload via tftp using "copy tftp flash2:" (2 denoting the member number in the stack) and to verify image is there you can do "dir flash2:" to see the contents of member 2's flash mem. Hope that helps!