Enabling IP NHRP on 3750

[Kiley Arena]

Hello all,

Please forgive me if I'm posting in the wrong area  - I have an issue that we hope to overcome - that of configuring multipoint GRE tunnels with ip nhrp on 3750 switches enabled for routinig.  There are no options to configure it as we see; we've enabled multicast routing thinking that would provide configuration options for our tunnel interfaces but, alas and alak, no luck. Does anyone know if this is even possible?

Thanks in advance very much for any guidance and enlightenment!!!

Kiley                  

[cadet alain · Accepted solution]

Hi,

This is not possible, this is a router feature.

Regards

Alain

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[Kiley Arena]

You know, I just hate it when I have that feeling that it wasn't going to work!!  Argggh!  Alain, thank you very much for your quick response, I appreciate it greatly!

We want to use multipoint GRE but, if we can't use ip nhrp on top of it, do you know what we can use in its place?

Thanks again.

Kiley

[Giuseppe Larosa]

Hello Kiley,

mGRE is not supported on LAN switches like C3750 as Alain has noted, it is not only a question of NHRP.

Besides this, even the use of p2p GRE tunnels on switches like these, is not recommended as it is likely process switched loading the main cpu of the switch instead of being processed in hardware.

Hope to help

Giuseppe