What is the difference between down and administratively down

BW is 1. The encapsulation on a serial interface is HDLC by default. The loopback can be set to test the link and the keepalive is 10 seconds by default. This is a Data Link layer keepalive that is sent between routers. If the timers are not exactly the same, the Data Link layer will not come up. The most important statistic of the show interface command is the output of the line and data-link protocol status.

Another thing to confirm is the state of the signals. Usually when the router interface is up and normal, all of the signals will show to be up.

This command is used to get a quick view of the status of all interfaces configured on the router. The status and protocol fields are quick indicators as to the state of the interface. Prior to marking an interface administratively up, confirm that it should be up. Typically for security reasons unused interfaces are administratively marked down.

This command would be recommended if the router was being re-deployed or decommissioned, and you wanted to make sure none of the old configuration elements were present when it either comes back online, or is decommissioned. Once the configuration is erased, upon reboot of the router, the user will be prompted to enter setup mode as if the router had come from the factory.

It might take a few minutes for the router to reload. Routers have an IP address on each interface that they have. We also have a serial interface. As explained in the introduction to WANs lesson , a serial interface might require a clock rate.

If you connect two routers back-to-back with serial links then the DCE side requires a clock rate. An alternative command that gives you a similar result is the show protocols command:. This router now has two active interfaces with IP addresses. You have now learned what the boot process of a Cisco IOS router looks like and how to erase the startup configuration so that you can start with a blank configuration.

We have also seen how to check what interfaces this router has, and how to configure IP addresses on each interface. The basic configuration of a Cisco catalyst switch is similar to this example. Hi Rene I have a question? When I try to change login local password from plain text password to encrypt password this message appears to me : ERROR: Can not have both a user password and a user secret.

Please choose one or the other. Ask a question or join the discussion by visiting our Community Forum. Skip to content Search for: Search. Lesson Contents. The system configuration message above will only appear if your router has no startup configuration. If your router asks you for a password and you have no idea what it is, you will have to perform a password recovery. All router interfaces are disabled by default.