Re: How are you configuring BFD timers?

[Mark Tinka <mark.tinka () seacom mu>]

On 21/Mar/18 19:10, Jason Lixfeld wrote:

> A few years ago I did some testing and found that the time between the transceiver detecting LOS and the routing 
> protocol (ISIS in this case) being informed that the link was down (triggering the recalculation) took longer than it 
> took BFD to signal ISIS to recalculate.

You also have the issues of:

  * Deciding whether you want to have a uniform standard when deploying
    BFD. If your standard is not to on dark links and should do lit
    links, you can quickly run into an administrative scenario as your
    network grows, and keeping track of which link is what re: BFD or
    not can be someone's untangling project 10 years later.

  * Circuit providers delivering hybrid links and not telling you
    because they are either afraid to or don't fully understand the
    scope of their (very large) network. In this case, you're told the
    link is dark, but somewhere along the path is their active gear.
    (not so) Strange, but true.

Mark.