to load the .bin image onto the switches at the same time

[veena_kompal]

I have around 20 catalyst 3560 switches and have got to upgrade the IOS on all these switches rather than upgrading these one by one. So could anyone suggest me how can I upgrade the IOS on all these cisco switches at the same time? I do have the .bin image file for the 3560 cisco switch and the TFTP server.

[glen.grant]

There is no way to do this unless you have management tool like ciscoworks or another OEM vendor. should take that long to do 20 switch anyway. Put your image on the tftp server and get them started , you rarely have a problem where they won't load .