Cisco ISR 4431 failed to start

[iscoFe_2021]

Dears,

I need a life saving help from you all regarding my ISR 4431 which i could not start or boot up. It shows the following mysterious display of random texts. Let me know what is causing this and how to remediate it.

[balaji.bandi · Accepted solution]

Looks like you using putty here - check the below comm settings and confirm?

Console terminal (an ASCII terminal or a PC running HyperTerminal or similar terminal emulation software) configured for 9600 baud, 8 data bits, 1 stop bit, no flow control, and no parity.

if that is set up as mentioned try different baud rates, is this new one or working one broken?

[iscoFe_2021]

Hello Balaji,

Thanks for the response. There is still the same problem even after applying the suggested parameter on putty even after setting up a different baud rate. The router was working fine few months back. Will there be any other solution for this? What do you recommend me to do next?

Thanks alot,

Sisay

[balaji.bandi]

next this i want to be test was Console cable, can you test is this cable work with any other device ?

[iscoFe_2021]

Yes, the console cable works fine on other devices including another ISR Router and other MLS Switches. What else this could possibly be? Would it be some kind of hardware problem or that is too soon to say?

[marce1000]

 - Could be that the boot image  is corrupt because of a bad flash file system. Below are 2 threads 1) Contains a procedure on how to  get into rommon 2) A procedure to boot the OS from a USB and restore a valid boot image on the flash :

  https://community.cisco.com/t5/routing/think-i-ve-bricked-an-isr-4331/td-p/3888622

  https://www.cisco.com/c/en/us/support/docs/routers/4000-series-integrated-services-routers/200678-Troubleshoot-Cisco-4000-Series-ISR-Stuck.html

 M.

[iscoFe_2021]

It worked after I changed it to a different baud rate on second time. Baud rate I set to was 115200. Thank you!