[j-nsp] Going Juniper

[Chris]

Hi,

On 10/04/2018 11:37 PM, mike+jnsp at willitsonline.com wrote:
> I know it can be set up and run like a champ and do some (undefined)
> number of gigabits without issue. What concerns me is that there are
> performance limitations in these software only platforms based on your
> processor/bus/card choices, and of course the performance of a software
> hash vs a hardware cam for forwarding table lookups. And usually
> (imho),  you hit the platform limits like a truck running into a brick
> wall. However, if I knew I was only going to have just a few gbps (3?),
> I likely would be very interested doing a live deployment. However, with
> that said, it certainly is interesting enough to investigate and I'd
> love to see your writeup. At a minimum it sounds very useful and I may
> use vMX for pre-deployment testing purposes.

The write up has been linked in one of the previous posts, so feel free 
to take a look at it there (I published it on my website as I suspect it 
will come in handy for other people trying to set this up).

As for the actual performance limitations of the vMX, I have not managed 
to hit them at all and I suspect I won't ever for the size of the 
networks that they are deployed in. When I was testing I got up to 40G 
of throughput through it which was much more than enough (using various 
packet sizes to simuluate real traffic), I didn't get to test any 
further though. The CPU difference between pushing 500M/60k PPS and 
9G/7m PPS was non existant - the graphs I have for my FPC on the vMX's 
is steady regardless of the traffic going through.

> On your mx104 you said cpu was pegged at %100 - operationally does this
> cause you any grief? How long does it take for your routes to recover
> after a peer flaps? (eg: your sending traffic to a dead peer before
> forwarding is updated to remove those). If you are logged in doing
> normal network stuff like looking up routes or making minor config
> updates, is the cli slogwash or can you move around and work?

There are a few problems:

* I use Ansible to deploy the configurations for network devices. The 
commit times are now quite bad (it can take almost 1.5 minutes) I had to 
adjust the timeout otherwise it would constantly fail.
* For the actual traffic going through the devices I don't have any issues
* Using the CLI to view routes, if you have a full table, can be a 
painful process.
* Traffic going to dead peers is a problem, I have given up taking full 
tables on all of my MX80/MX104 devices. Sometimes this could mean an 
outage of over 30 minutes if BGP is flapping as well in my case.
* Since I use Ansible to deploy the configs, I don't touch the CLI a lot 
directly. When I do, its responsive enough when making changes/viewing 
the config, the slow part is the commit process as well as viewing routes.

Since the MX104 has user replacable RE's I really wish Juniper would at 
least offer a different option with a more beefy CPU/RAM but I don't 
think that would ever happen...