[External] Re: uPRF strict more

Thu Sep 30 15:56:26 UTC 2021

On Thu, Sep 30, 2021 at 12:08 AM Mark Tinka <mark at tinka.africa> wrote:
> If you don't plan to run a full BGP table on a device, don't enable uRPF, even loose-mode.

At least in Ciscoland, loose URPF checks will pass if you have a
default route. So I do not think it could result in inadvertent
blackholing of traffic.

What it does allow is for *deliberate* blackholing for traffic; if you
null-route a prefix, you now block incoming traffic from that subnet
as well. This can be useful and it is how we are using URPF.

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Hunter Fuller (they)
Router Jockey
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