Customer forgot the console password on P (NE80E) router on MPLS network, even no vty and ssh was working to troubleshoot. It was critical to recover because no method was documented.
Proposed solution checked by customer in their LAB, then implemented into the P (NE80E) router on MPLS network.
If you are not able to login through console, reboot the card and press CTRL+B to enter into the boot menu.
After entering the bootmenu you will find options.From the menu, select 8 to get the list of files present in CFcard.
After selecting 8 you will see the list of files.Among these file identify the vrpcfg.zip file and note down the filename accurately as we will need the name later.
Now at the main boot menu press CTRL+Z to enter the Hidden Menu.
From the hidden menu shown above select 4 to rename the vrpcfg file. After selecting 4 you will be shown window.
After the above step enter vrpcfg filename and rename the file to another name e.g. Huawei.After the file is renamed successfully you will be shown hidden menu,
now press 8 to come back to main menu and then press 8 to list the files in CFcard
From the list of files verify that vrpcfg.zip is not present there. It should not be there.
Then press 10 to reboot the router.Now When router is booted completely,
it will become a fresh router. Now check the files in the CFcard.The file Huawei.zip should be there.
Now take the Huawei.zip file into your laptop using ftp or tftp.
When you will open the configuration file in notepad you will find some configuration.
Remove the configuration line between “user-interface con 0” and “user-interface aux 0”. Now save this in notepad and change the name of file to “vrpcfg.zip” from “Huawei.zip”.
Now upload this vrpcfg.zip to router using ftp or tftp.
After this run the command “startup saved-configuration cfcard:/vrpcfg.zip”.
Now reboot the router. After completion of reboot the router will not prompt for console password.
It was total "human mistake".
Customer had to be managed all passwords. This was total "human mistake" in an apex telecom operator.
Please advise,customer to manage its all username|password.