I have a Cisco 2514 acting as an Internet gateway in a CCNA study lab
setup. I have a Comcast cable modem connect to e1. The 2514 is
configured as a DHCP client to get its IP addressing info from Comcast.
This all works fine.
Occasionally when I change configurations in the lab I want to force
the 2514 to renew its DHCP lease info from Comcast. The only way I
have been able to do this is to power cycle the cable modem. Then
"shutdown", "no shutdown" interface e1. Simply shutting down
the interface and bringing it back up does not cause the router to get
a fresh IP address on e1 unless I power cycle the modem first.
Is there a better way to do this? It seems to that there would be a
direct unambiguous command to renew the DHCP client, something akin to
"ipconfig /renew" in windows. But, I'm new to this and may not
be thinking in the correct context.