INTERFACE NULL0 AND INTERFACE LOOPBACK

[jabbar154]

How many number of interface null0 and interface loopback could be defined on a router.

[m.mazurek]

As an example:

#interface loopback ?

<0-2147483647> Loopback interface number

#interface null 0?

<0-0>

hth

mazek

[Harold Ritter · Accepted solution]

There can only be one null interface. The null0 is like a bit bucket therefore you don't need more than one.

As far as the number of loopback interfaces, it should only be limited by the number of IDBs (interface data block) supported by the IOS you run and the memory you have on the router, which would be pretty high in any case.

Hope this helps,