I have 3 routers setup in my lab for testing. One router for the frameswitch and the other 2 are DTE devices(RouterA and B). I followed the serial port FAQ's and the configuration work fine until i power down the routers. I can't ping the serial interface's anymore within router A and B. I was able to ping within all routers before what happened? It seems that the inverse-arp is not working. Any troubleshooting suggestions. Please help, thanks.