[j-nsp] EX4200 questions

[Bernhard Schmidt]

Chris Evans <chrisccnpspam2 at gmail.com> wrote:

Hi Chris,

many thanks for your answer...

> It sounds like the EX4200 would be a fit for you if you're only doing l2, as
> you mentioned it doesn't have a big FIB for a large amount of routes.. You
> said that 16k routes would suffice for you, so perhaps you are doing L3 but
> you're not importing full route feeds in this network area. I somehow
> remember only testing to 14K and it started to complain about the FIB being
> full.. I would double check that capacity limit, I think it changed on
> versions of code.

A system able to carry one (or more) full routing tables would be a lot
more expensive, so we are going to switch the transit VLANs through the
box to terminate on the 6500, while doing routing for the exchange
traffic. This will only carry a few dozen customer routes and the
peering prefixes, so 16k should be enough for now.

> As for SPT, you could use VSTP (and use Rapid-PVST on Cisco side) or MSTP.
> MSTP inter operates correctly, VSTP does 99%. VSTP works fully except for
> VLAN1. Cisco listens to the IEEE 802.1D MAC-Address for this VLAN, but VSTP
> on JUNOS only sends to the Cisco proprietary MAC so its messages get
> ignored. I hope you aren't using VLAN 1 and are pruning it from your trunks.
> If you do this you will be okay.. VSTP operates exactly like Rapid-PVSTs in
> that there is a tree built for every VLAN.

Thanks, we're not using VLAN 1, so that should be safe then.

Another possible approach would be to facilitate EoMPLS to forward the
transit ports into the core network. Would be a lot nicer regarding
architecture, but unfortunately the 6500 can't do EoMPLS plus L3 on the
same VLAN, so it would require a loopback connection there. And we have
two core routers.

Can Juniper/the MX do something like that

                   Transit Port
                        |
             +----------+--------+
             |   Local switching |
             +--+------------+---+
                | EoMPLS     | EoMPLS
                |            |
             +-------+   +-------+
             | core1 |   | core2 |
             +-------+   +-------+

without looped ports?

Best Regards,
Bernhard