3560G con0 loop.... please help!!

lee.foley · ‎04-19-2009

Hi

I had a switch go down recently. In replacing said switch i dropped the config onto the replacement, copied running config to start and reloaded.

However, when it had booted back up, i was unable to connect back onto the switch via the console cable.

Its simply states that Con0 is now available, press return to get started. However when i hit return it flashes Authentication failed and then loops back to Con0 is now available, press return to get started.

Can anybody offer me advice on

a)what could be a possible cause of this and

b) how i could resolve the problem.

Thanks in advance

Lee

jimmysands73_2 · ‎04-19-2009

I am new to this, but I think the issue might be you might be attempting to have your sw attempt to reach a radius or tacacs for auth (bad for a local console port). You need to set it for local atuh (I believe its 'login local'). I could be totally wrong in my observation though.

To fix it boot your sw (if you have that luxury)...I followed this guide, http://www.petri.co.il/csc_how_to_recover_lost_password_on_cisco_switch.htm, but you can find something on ciscos site also, and change/observe your line con 0 config that way.

Cheers

Jimmy

lee.foley · ‎04-19-2009

Thanks Jimmy

I'll give that a try and feedback.

Thanks again

Lee

davy.timmermans · ‎04-20-2009

If you are able to reboot the switch I would do the following:

reboot the switch

press on the mode button in order to come in rommon mode

switch: flash_init

switch: rename flash:config.text flash.config.text.temp

switch:boot

The switch will boot without any configuration because it can't find config.text.

Answer 'no' for initial configuration

switch>en

switch#copy flash:config.text.temp run

switch#wr

and then you've to look what's configured

aaa new-model

aaa authentication login default local

or

line con 0

login local

if this is true> check if there is a

user xxx secret/password xxxx is configured

I suspect that no user x secret xxx is configured.

Else you can help by posting all related config