lmfao you really thought you where going to get the answer
They are configured dynamically and are saved in the running configuration.
The FastEthernet interface of R1 is disabled. One of the default routes is configured incorrectly. A routing protocol is not configured on both routers. The default gateway has not been configured on both routers.
there may be the issue with the layer 2 protocol like hdlc or ppp is not configured or wrongly configured if the interface is serial interface.
When the interface is functioning as a DCE device
switches will monitor the frames sent from each interface and it will store the source MAC-addresses in a table. fm
The interface is configured as a DCE device.
2
sometimes when interface configured with a static IP address, which is not correct, the host does not communicate to the port, and switch has no MAC address. I've seen it just two days ago - had an Linux appliance with a static IP address configured on the interface. Plugged interface to the switch, port says "Connected", but no MAC address in the CAM table. After I changed an IP address to whatever it should be for the VLAN - NIC started to communicate, and MAC address appears on the port.
To allow the subnet configured on that interface to be advertised through a dynamic routing protocol without having that interface participate in the protocol.
All configured VLANs will be allowed across the trunk.
inet
ifconfig