Authentication error

Question

I have set the username **** privilege 5 secret **** & applied aaa via console. now unable to access switch through console. After entering enable showing authentication error.

can someone help me to resolve the issue.

Configuration:

config for console:

username cisco privilege 5 secret cisco 
line vty 0 4 login local 
end 

config for aaa

aaa new-model 
aaa authentication login default group tacacs+ local 
aaa authentication enable default group tacacs+ enable 
aaa authorization commands 1 default group tacacs+ local 
aaa authorization commands 15 default group tacacs+ local 
aaa accounting exec default start-stop group tacacs+ 
aaa accounting commands 1 default start-stop group tacacs+ 
aaa accounting commands 15 default start-stop group tacacs+ 

aaa accounting network default start-stop group tacacs+

Answer 1

After reviewing your configuration it appears that you applied login local only the VTY lines and not the console port.

Since you no longer have access to the device you will need to initate a password recovery for the device following the instructions listed here. This will allow you to log into the device and make changes.

You will then need to add the following configurations:

line con 0

login local

Once that has been added you should be able to login via the console port using a locally created account.

Two more small pieces of advice:

1. Don't use Cisco as your username. Always create a unique username for your organization. This adds a small layer of obscurity to your security posture.
2. Don't forget to perform a copy run start after you apply login local to your console port. You don't want to reboot later on and realize that you can no longer console in.