Lost local username database after IOS downgrade
I had to downgrade one of the routers at work (a 3825) from IOS 15.1(4)M5 to a 12.4T train. After the router was reloaded and came back up, I found that it had lost the username/password database (so I was locked out of the router). After consoling into the router and changing the config register to ignore the startup config, I was able to actually look at what had happened to the config...the whole database was gone! the only username that was left was the "ip ftp password xxxx".
Has this ever happened to anyone else?