RE: PMTU-D: remember, your load balancer is broken

[Deepak Jain <deepak () ai net>]

This can be done on FE interfaces too. Running Cisco FE interfaces
back-to-back at 4470 seems to work. I wanted to say that the GE interface
below doesn't work with large frames with a certain other vendor's
hardware the couple of times we've tried it, and that the default was in
fact 1500 for probably that reason.

One-off solutions tend to be more trouble than they are worth in big
networks.

Deepak Jain
AiNET

On Wed, 14 Jun 2000 jhsu () mur com wrote:

>  :
>  : Then again, at least some Cisco gear doesn't think that.
>  :
>  : perdition>sh in g0/1
>  : GigabitEthernet0/1 is up, line protocol is up
>  :   Hardware is Gigabit Ethernet, address is 00d0.7966.eeae (bia 00d0.7966.eeae)
>  :   MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec, rely 255/255, load 24/255
>
> the last i checked, 1500 was the default.  given the right hw & sw,
> MTU can be adjusted upward. i seem to remember seeing it demonstrated
> on 12000 gear.
>
> there is a draft [draft-kaplan-isis-ext-eth-02.txt] that discusses
> some extensions useful to support large frames. these extensions- again, 
> the last i checked- were supported by cisco, and other vendors.
>
> as always, contact your authorized support rep when in doubt.
>
> ymmv,
>
> _k