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New Member

back-to-back ethernet port

how to configure back-to-back ethernet port? and what type of cable will i use. thanks


Re: back-to-back ethernet port

If i correctly understood ur question then,the cable to be used depends on the devices.

connecting two ethernet port of two switches or two routers require cross cable and a router and switch require straight cable... :)

New Member

Re: back-to-back ethernet port

yes. i will connect two routers back-to-back using gig port. what should be the configuration then?


Re: back-to-back ethernet port

HI Korbenda, [Pls Rate if HELPS]

You should use Cross cable to connect the router back to back.

Normally the parameter in configuration includes are:

>>ip address


>>speed settings

>>duplex settings

Pls Rate if HELPS

Best Regards,

Guru Prasad R

New Member

Re: back-to-back ethernet port

actually i just want to back-to-back connect 7206 and 2851 router using its gig port. i put an ip address but to my amaze the port did not come up. I tried to back to back two 7206 router using its gig port and it works. why? is there anything i need to add in my configuration for the 2851 router? thanks.

Re: back-to-back ethernet port

It is not mandatory to have an IP address on the ethernet interface for it to come up.

Make sure the interfaces are not administratively shutdown as they are by default.

As suggested above you may also try to change the speed and duplex settings and see if the port comes up



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