Routing Jumbo MTU packets with ASR1002 router

[pweinhold]

Hello,

We have a requirement to route Jumbo MTU packets for a customer. This customer currently connects to us via a 3750 switch. We found out that a 3750 wouldn't route Jumbo packets, so now we want to swap that 3750 switch out for an ASR1002 router. Our understanding was that an ASR router would route Jumbo packets. However, I'm now testing the router in a lab and I can't figure out how to configure that on the router. For example, when I try to set the MTU on an interface on the router, it only gives me the option of going up to 1500 bytes. See the following output:

Router_B(config)#int gi 0/0/0

Router_B(config-if)#ip mtu ?

  <68-1500>  MTU (bytes)

Is there some global config to allow for a Jumbo MTU size?

Thanks.

[cminton_ERS · Accepted solution]

try

config t 

int gi0/0/0

mtu  ?

-i know from switching side some of the newer blades we ordered on the 6509s didnt allow the jumbo mtu option, we have to use our old blades to set mtu higher than 1500, i am not sure on the ASRs

HTH

[pweinhold]

That did it! It was "mtu" instead of "ip mtu". See here:

Router_B(config)#int gi 0/0/0

Router_B(config-if)#mtu ?

  <1500-9216>  MTU size in bytes

Thanks very much.