A Command query

Hi All
I am interested to know one thing. Assuming that I have a brand new, totally unconfigured router. Some serial interfaces are connected and some are not.

What is the command to check, by using the CLI, which Interfaces are connected and which are not?

Thanks in advance,

Milan Chatterjee

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Comments

mattau

show ip interface brief will show you what you have and if they are currently up or down

okplaya

If the router is brand new, without any configuration, all of the interfaces will show "administratively down" regardless if a cable is connected or not.

You will need to perform a "no shutdown" from interface configuration mode on each interface you'd like to enable.

Switches are the exact opposite in that all ports will be open by default.

HTH

milanchatterjee

okplaya wrote: »

If the router is brand new, without any configuration, all of the interfaces will show "administratively down" regardless if a cable is connected or not.

Hi Okplaya and others. It is showing so as you have mentioned.

You will need to perform a "no shutdown" from interface configuration mode on each interface you'd like to enable.

I would like to know, which 3 Interfaces are serially connected, out of the 7 interfaces, USING THE CLI WITHOUT PHYSICALLY CHECKING the interface modules of the routers.

Switches are the exact opposite in that all ports will be open by default.

HTH

Thanks in advance

Milan Chatterjee

milanchatterjee

PLease ignore my last message:

If the router is brand new, without any configuration, all of the interfaces will show "administratively down" regardless if a cable is connected or not.

Hi Okplaya and others. It is showing so as you have mentioned.

You will need to perform a "no shutdown" from interface configuration mode on each interface you'd like to enable.

I would like to know, which 3 Interfaces are serially connected, out of the 7 interfaces, USING THE CLI WITHOUT PHYSICALLY CHECKING the interface modules of the routers.

Switches are the exact opposite in that all ports will be open by default.

HTH
Thanks in advance

Milan Chatterjee

chmorin

milanchatterjee wrote: »

I would like to know, which 3 Interfaces are serially connected, out of the 7 interfaces, USING THE CLI WITHOUT PHYSICALLY CHECKING the interface modules of the routers.

Milan Chatterjee

Show ip int brief will give you a view of all of the slots/interfaces you currently have configurable on the router. For example:

Router#show ip int brief
Interface              IP-Address      OK? Method Status                Protocol
 
FastEthernet0/0        unassigned      YES manual administratively down down
 
FastEthernet0/1        unassigned      YES manual administratively down down
 
Serial0/0/0            unassigned      YES manual administratively down down
 
Serial0/3/0            unassigned      YES manual administratively down down
 
Serial0/3/1            unassigned      YES manual administratively down down
 
Serial1/0              unassigned      YES manual administratively down down
 
Serial1/1              unassigned      YES manual administratively down down
 
Serial1/2              unassigned      YES manual administratively down down
 
Serial1/3              unassigned      YES manual administratively down down
 
Serial1/4              unassigned      YES manual administratively down down
 
Serial1/5              unassigned      YES manual administratively down down
 
Serial1/6              unassigned      YES manual administratively down down
 
Serial1/7              unassigned      YES manual administratively down down
 
Vlan1                  unassigned      YES manual administratively down down
Router#
Router#

Here you can see I have something in s0/0/x, s0/3/x, and s1/x (Network Module). Status tells you if the line is physically connected. Protocol tells you if it has been logically configured properly to establish a logical connection connection.

So lets take the same device and plug in something randomly here and there, no shut the interfaces, and run the command again:

Router#show ip int brief
Interface              IP-Address      OK? Method Status                Protocol
 
FastEthernet0/0        unassigned      YES manual administratively down down
 
FastEthernet0/1        unassigned      YES manual administratively down down
 
Serial0/0/0            unassigned      YES manual administratively down down
 
Serial0/3/0            unassigned      YES manual up                    down
 
Serial0/3/1            unassigned      YES manual up                    down
 
Serial1/0              unassigned      YES manual up                    down
 
Serial1/1              unassigned      YES manual administratively down down
 
Serial1/2              unassigned      YES manual administratively down down
 
Serial1/3              unassigned      YES manual administratively down down
 
Serial1/4              unassigned      YES manual administratively down down
 
Serial1/5              unassigned      YES manual administratively down down
 
Serial1/6              unassigned      YES manual administratively down down
 
Serial1/7              unassigned      YES manual administratively down down
 
Vlan1                  unassigned      YES manual administratively down down
Router#

As you can see, s0/3/0, s0/3/1, and s1/0 are now physically connected.

Does this answer your question? You can also run "show hardware" and get some more information about what you have in your router.

milanchatterjee

If the router is brand new, without any configuration, all of the interfaces will show "administratively down" regardless if a cable is connected or not.

Hi
Thanks for your reply. This is the actual thing which I was interested to know. So, I have to be physically present at the router to see which serial interfaces are connected in a total virgin router.

Milan