[j-nsp] Redundancy with MX

[Saku Ytti]

On (2013-01-24 17:53 -0500), Stephen Hon wrote:

> I'm wondering though, would dividing some of the routing duties into
> logical systems help to protect from a massive system-wide problem? From
> what I understand the logical systems spin up their own set of processes
> and have their own configuration so it would seem that there could be some
> level of protection.

I would personally avoid lsys as much as possible. I would not out-right
ban the feature, but I would want extremely good justification for it, I
haven't figured out one yet, but I'm sure there are reasons to run it.

But you are right, each lsys runs own copy of RPD. And this is probably
only way to use more than 4GB of memory today.
I'm sure there are some failure scenarios where fault won't propagate
across LSYS borders. Like maybe one LSYS is VPN BGP and another is INET
BGP, and when some UPDATE from DFZ crashes your INET RPD possibly VPN RPD
is alive and kicking.

Still I'd be afraid that the added complexity bites me more often than
saves me.

-- 
  ++ytti