diff between serial0/0 and serial0 2

[paulw]

I have a config of a router that is currently in use IOS11.2
which shows all the interfaces as interface <type>0/0
e.g Interface Serial0/0

The subinterfaces look like
Interface Serial0/0.900

I am configuring a replacement router running IOS11.3 which shows all the interfaces as interface <type>0
e.g Interface Serial0

The subinterfaces look like
Interface Serial0.900

I can't find an explanation of why the difference. Can someone maybe explain it to me.

Thanks
Paulw

 

[eurobadger]

Hi Paul


Depends on the router.

For instance the 2500s were equipped with a single ethernet port, this was ethernet 0. In the 2621 on the other hand there are 2 built-in (fast) ethernet ports and these are fastethernet 0/0 and 0/1.

Hope that helps. More info on

http://www.cisco.com

EB

 

[tschouten]

The easiest way to think of it is this, card slot 0, port 0. The reason Cisco started using that was to differentiate the location of ports on certain cards for modular devices. It carries over in other models.

Say you have two card slots 0 and 1. On each card slot you have two fastethernet ports. You would look for it by the name fastethernet 0/0, fastethernet 0/1, fastethernet 1/0, fastethernet 1/1.

Hope that helps explain it a bit. I'm basically saying the same thing eurobadger said just a little more in depth.

 

[paulw]

Thanks

It all makes sense when someone points it out. The router I'm configuring is a Cisco4000 I'm not sure what's currently in use and the 4000 doesn't use slots like say a 1700 series does.

Thanks
Guys

Now I'll be able to sleep at night