2 Replies Latest reply: Feb 14, 2019 3:59 PM by sedvalson RSS

    Cisco 3850 USB IOS Upgrade


      I uploaded a new IOS .bin on to a single switch while it was connected to our network. I had trouble because I was using a USB for the first time, and I kept getting an error saying I needed an ip domain-name before I could save the RSA token. I set the domain name and everything seemed to work fine, but when the switch reloaded it would no longer let me log in. I couldn't SSH or console in using my ACS login and I could no longer ping the switch. All of the users were up and able to use there computers and phones and the switch appeared to boot up correctly, but I cannot log in. The switch also appears to be down on solarwinds. I dont know where to go from here and my users need minimal down time so I am hesitant to try a password recovery if I am not sure it will work.

        • 1. Re: Cisco 3850 USB IOS Upgrade

          Hi Sedvalson


          You do not need a domain name. Here is a example from a router. I think you will have to clear the configuration and start again.


          no ip ssh version is 1 & 2



          username conwyn privilege 15 password cisco

          crypto key generate rsa usage-keys label myrsakey modulus 768

          ip ssh authentication-retries 5

          ip ssh rsa keypair-name myrsakey

          line vty 0 4

          login local (no need for aaa new-model)

          transport input ssh



          SSHClient#ssh -l conwyn




          • 2. Re: Cisco 3850 USB IOS Upgrade

            My IOS instructions are as follows

            #software clean

            #dir usbflash0:

            #copy usbflash0:/(IOS name) flash

            then I save the RSA token, however before this step it is telling me I need a domain name. How do I complete this step without one? Do you know why it would cause ACS to not function?