default interface status

[fsoffia]

hallo

what is the default status for an interface on a router ?

"down, line protocol down" or "administratively down, line protocol down" ?

[prathapccie]

This is the default in router "administratively down, line protocol down

[stephtchoko]

Good day,

The default status of interface on a router is :

interface down, line protocol down. if the interface is not connect to a switch.

http://www.cisco.com/en/US/products/sw/iosswrel/ps1818/products_getting_started_guide_chapter09186a00800879e9.html

Don't forget to rate this post.

Regards.

[sean]

You normally don't see the admin down unless somebody has gone into interface config and issued the shut command.

[Richard Burts]

Actually it depends on how you brng the router up. If you boot a router that has no startup config (or with config-register set to 0x2142 so that it ignores an existing startup config) the router will ask if you want to run the startup dialog. If you respond no, then the IOS will put each of the physical interfaces into administratively down state - so that appears to be the default state.

If you do go through the startup dialog then you have opportunity to set interfaces as you want (in use/up or not in use/administratively down). And if you get a router with SDM installed and you use SDM then you may do things with interface state. But I would believe that these are no longer default interface state but state after someone has entered commands.

HTH

Rick

[azi123]

Do you have any idea why the default state was/is shut down? Any power concern?

[Joseph W. Doherty]

Regarding default state, just want to mention, when I boot up a "clean" L2 switch, L3 switch or router (w/ config 2102 and bypassing initial config), L2 ports usually are set to down/down while L3 usually are set to administratively down/down.

My guess L2 ports might be ready to go (i.e. not administratively down) possibly to "mimic" unmanaged hubs and/or switches.

L3 ports, though, require things like an IP address, so it sort of makes sense they require an explicit "no shut" when they have be correctly configured for their L3 usage.

A PT 3560

Switch>sh ip int b
Interface              IP-Address      OK? Method Status                Protocol 
FastEthernet0/1        unassigned      YES unset  down                  down 
FastEthernet0/2        unassigned      YES unset  down                  down 
FastEthernet0/3        unassigned      YES unset  down                  down 
FastEthernet0/4        unassigned      YES unset  down                  down 
FastEthernet0/5        unassigned      YES unset  down                  down 
FastEthernet0/6        unassigned      YES unset  down                  down 
FastEthernet0/7        unassigned      YES unset  down                  down 
FastEthernet0/8        unassigned      YES unset  down                  down 
FastEthernet0/9        unassigned      YES unset  down                  down 
FastEthernet0/10       unassigned      YES unset  down                  down 
FastEthernet0/11       unassigned      YES unset  down                  down 
FastEthernet0/12       unassigned      YES unset  down                  down 
FastEthernet0/13       unassigned      YES unset  down                  down 
FastEthernet0/14       unassigned      YES unset  down                  down 
FastEthernet0/15       unassigned      YES unset  down                  down 
FastEthernet0/16       unassigned      YES unset  down                  down 
FastEthernet0/17       unassigned      YES unset  down                  down 
FastEthernet0/18       unassigned      YES unset  down                  down 
FastEthernet0/19       unassigned      YES unset  down                  down 
FastEthernet0/20       unassigned      YES unset  down                  down 
FastEthernet0/21       unassigned      YES unset  down                  down 
FastEthernet0/22       unassigned      YES unset  down                  down 
FastEthernet0/23       unassigned      YES unset  down                  down 
FastEthernet0/24       unassigned      YES unset  down                  down 
GigabitEthernet0/1     unassigned      YES unset  down                  down 
GigabitEthernet0/2     unassigned      YES unset  down                  down 
Vlan1                  unassigned      YES unset  administratively down down

A PT 3650

Switch>sh ip int b
Interface              IP-Address      OK? Method Status                Protocol 
GigabitEthernet1/0/1   unassigned      YES unset  down                  down 
GigabitEthernet1/0/2   unassigned      YES unset  down                  down 
GigabitEthernet1/0/3   unassigned      YES unset  down                  down 
GigabitEthernet1/0/4   unassigned      YES unset  down                  down 
GigabitEthernet1/0/5   unassigned      YES unset  down                  down 
GigabitEthernet1/0/6   unassigned      YES unset  down                  down 
GigabitEthernet1/0/7   unassigned      YES unset  down                  down 
GigabitEthernet1/0/8   unassigned      YES unset  down                  down 
GigabitEthernet1/0/9   unassigned      YES unset  down                  down 
GigabitEthernet1/0/10  unassigned      YES unset  down                  down 
GigabitEthernet1/0/11  unassigned      YES unset  down                  down 
GigabitEthernet1/0/12  unassigned      YES unset  down                  down 
GigabitEthernet1/0/13  unassigned      YES unset  down                  down 
GigabitEthernet1/0/14  unassigned      YES unset  down                  down 
GigabitEthernet1/0/15  unassigned      YES unset  down                  down 
GigabitEthernet1/0/16  unassigned      YES unset  down                  down 
GigabitEthernet1/0/17  unassigned      YES unset  down                  down 
GigabitEthernet1/0/18  unassigned      YES unset  down                  down 
GigabitEthernet1/0/19  unassigned      YES unset  down                  down 
GigabitEthernet1/0/20  unassigned      YES unset  down                  down 
GigabitEthernet1/0/21  unassigned      YES unset  down                  down 
GigabitEthernet1/0/22  unassigned      YES unset  down                  down 
GigabitEthernet1/0/23  unassigned      YES unset  down                  down 
GigabitEthernet1/0/24  unassigned      YES unset  down                  down 
GigabitEthernet1/1/1   unassigned      YES unset  down                  down 
GigabitEthernet1/1/2   unassigned      YES unset  down                  down 
GigabitEthernet1/1/3   unassigned      YES unset  down                  down 
GigabitEthernet1/1/4   unassigned      YES unset  down                  down 
Vlan1                  unassigned      YES unset  administratively down down