Basically, up/down means the port is available for a cable/connection, but doesn’t have one. Check the cable, or other computer.
What does up up mean in Cisco?
Show Interfaces Command and Interface Status Codes
| Line Status | Protocol Status | Possible Root Cause |
|---|---|---|
| Up | Down | And interface is not expected on physical interfaces. |
| Down | Down error disabled | Port security has disabled the interface. |
| Up | Up | The interface is working. |
What is the meaning of the up up part of the output?
The “up/up” output on the same line as the interface name indicates the Layer 1/Layer 2 interface state. This is the same as the Status and Protocol columns in the equivalent IPv4 command. The output displays two configured IPv6 addresses per interface.
What does a link status of Up Up indicate?
If the link status displays UP, it means that the connection is complete and a session can be started.
What does interface status mean?
The first line of the output indicates the working state of the interface. The first status code (known as line status) indicates that the Layer 1 is working (FastEthernet0/1 is up). Finally, the word at the end of the line indicates the working state of the interface (connected in our case).
Is up line protocol is down?
FastEthernet0 is up, line protocol is down: In this case, Physical layer is operational. The line protocol being down indicates a clocking or framing problem. Ethernet0 is administratively down, line protocol is down: This output indicates that a local interface has been manually shut down using the shutdown command.
What is the purpose of the banner motd command?
Description. This command specifies the message that is displayed as the Message Of The Day, the very first message displayed to an incoming connection. This command defines only the message; the motd-banner command enables or disables the display.
What is Cisco serial interface?
Serial interfaces can be connected using the cable V. 35 DTE and DCE cables. The interface to which DTE end is connected act as Data Terminal Equipment and the end where DCE connected acts as Data Communication Equipment. Data Communication End provides clock rate and allocates bandwidth to the Data Terminal Equipment.
What is serial interface in router?
Serial interfaces are used by ISP to provide WAN connections as a frame relay, T1, T3, etc. The port used is V.35 or RS232. Ethernet interfaces are used in LAN and WAN connections (RJ45).
What is link up link down?
Answer: The “Link Up” or “Link Down” SNMP Trap monitors the port operating status of a switch (SNMP Client). If an Ethernet cable is plugged into a port, or a cable is removed, then the SNMP Client will send a corresponding “Link Up” or “Link Down” notification to a network management station (SNMP Manager).
What triggers a serial interface to transition to the down state?
For each encapsulation type, a certain number of keepalives ignored by a peer triggers the serial interface to transition to the down state. For HDLC encapsulation, three ignored keepalives causes the interface to be brought down. For PPP encapsulation, five ignored keepalives causes the interface to be brought down.
What is a serial interface used for?
Serial interfaces are used to communicate with other local Cisco Routers or to establish a connection to the WAN through a CSU/DSU device.
What does it mean when the interface shows up down?
And if the interface shows up up then we have physical connectivity and the ability to transmit and receive on the interface. So down down indicates a problem with the connection. And up down indicates that we believe that we have a valid connection but no ability to transmit and receive.
Why is the line protocol down on this interface?
On a serial interface like this line is up line protocol is down is an indication that keepalives have failed. There are several things that can cause this. Paul mentions clocking and that certainly can be a cause.
