Two BGP peering sessions on single Comcast Fiber Connection?

Leo Bicknell bicknell at
Fri Oct 14 16:47:33 UTC 2016

In a message written on Thu, Oct 13, 2016 at 05:48:18PM +0000, rar wrote:
> The goal is to keep the single BGP router from being a single point of failure.

I don't really understand the failure analysis / uptime calculation.

There is one router on the Comcast side, which is a single point of

There is one circuit to your prem, which is a single point of failure.

To connect two routers on your end you must terminate the circuit
in a switch, which is a single point of failure.

And yet, in the face of all that somehow running two routers with
two BGP sessions on your end increases your uptime?

The only way that would even remotely make sense is if the routers
in question were horribly broken / mismanaged so (had to be?) reboot(ed)
on a regular basis.  However if uptime is so important using gear
with that property makes no sense!

I'm pretty sure without actually doing the math that you'll be more
reliable with a single quality router (elminiation of complexity),
and that if you really need maximum uptime that you had better get
a second circuit, on a diverse path, into a different router probably
from a different carrier.

Leo Bicknell - bicknell at
PGP keys at
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