Re: Please don't use 11.1-MFIB with DVMRP-mode tunnels

[Steve Shultz <]

It is a common mistake to have "ip dvmrp unicast-routing" on dvmrp
tunnels. People should check their configs and remove dvmrp
unicast-routing on dvmrp tunnels.

interface tunnel 0
ip dvmrp unicast-routing
tunnel mode dvmrp

					Steve Shultz
					NASA Internet

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On Tue, 31 Mar 1998, Bill Fenner wrote:

> Date: Tue, 31 Mar 1998 13:35:48 PST
> From: Bill Fenner fenner@localhost
>, mbone@localhost
> Cc: fenner@localhost
> Subject: Please don't use 11.1-MFIB with DVMRP-mode tunnels
> 
> Folks,
> 
>   Please don't use the 11.1-MFIB branch with DVMRP-mode tunnels.  There is
> a bug (which Cisco knows about and is working on) which can cause DVMRP-mode
> tunnels to black hole all traffic flowing through them.  Route exchange
> still works, so traffic gets routed through them; however forwarding is
> broken and will black hole.
> 
>   Until Cisco has a fix available, please move your DVMRP-mode tunnels off
> of your 11.1-MFIB routers, or run something other than 11.1-MFIB on them.
> Otherwise, you can potentially cause black holes (this explains several of
> the MBone's current problems).
> 
> Thanks,
>   Bill
>