isr 4300 how to put up the giga 0/0/1 without cable connected

[Roberto Casagrande]

Hi and thanks for support,

in the hold router I knew the command to bringing the fastethernet state up , for example no autostate or not keeplive or keeplive (don't remember).

Which is the commands use in ISR router for put up the Giga without cable connected ?

thanks a lot

Roberto

[Georg Pauwen]

Hello,

it used to be 'loopback' interface configuration mode, not sure if that command is valid on the 4331...

4331#conf t

4331(config)#interface GigabitEthernet0/0/1

4331(config-if)#loopback ?

[Roberto Casagrande]

thanks , I tried but status and protocol down down

[Leo Laohoo]

no keepalive

[Giuseppe Larosa · Accepted solution]

Hello Roberto,

the old ethernet and some fast ethernet interfaces could be put up/up with

int fa0/0

no keepalive

!

even if no cable was connected to them

I don't think modern GE ports can support this trick. I used it 16 years ago or even more.

If you need a logical interface to be used for testing IP connectivity you can use a loopback interface.

Cisco routers support multiple loopback interfaces and they support also subnet masks not only /32.

This is the common way of performing tests now.

the loopback command  in a physical interface should be supported on serial, ATM and POS interfaces for troubleshooting purposes.

Hope to help

Giuseppe

[Roberto Casagrande]

thanks a lot Giuseppe,
yes it's a best way for testing. I liked that command for not change the configuration and then come back after test again.