Tuesday, June 9, 2009

IE SP Vol 2 Lab 2

Ok, change of page--I decided to attack IE vol 2 lab 2 again.

Layer 2:
No issues, not even with PPPoE--yay!

IGP:
No issues

BGP:
No issues

MPLS:
No issues

VPN:
Ahhh, now here was a nice complicated VPN scenario. Not too many tricks up their sleeves, but i definitely had to do some thinking.

Send-labels was not required, even though the two ASs weren't running MPLS. This is because the vpnv4 routers were back to back so an ipv4 lookup was possible at each AS edge router. Now if the AS edge routers weren't vpnv4 routers, they wouldn't understand the vpn tag and would have dropped the packet. If that were the case, send-labels (and next-hop-unchanged) would have been necessary.

I had a little bit of an issue with VRF Internet Access, but I eventually got it worked out. A stupid mistake where I did "ip nat source" instead of "ip nat inside source".

Finally, the solutions guide used an export map which sets bgp communities and then filters them on the PE routers to filter the management interfaces. Ugh, I thought that was an ugly method. I went with an import map that just filtered the ips out on the PEs without having to mess with communities.

Multicast:
They went with a tunnel, but my mdt worked just fine too.

QoS:
I just couldn't get mpls marking to work. I tried topmost and imposition, and verified the packets were getting marked on their way out, but the never showed up as marked on the other side. The solutions agreed wtih my first method. I'm gonna write this off as a dynamips frame switch issue.

I'm just going to review the rest of the lab since I pretty much know how to do these. Besides, the Management and Services section is more of an easter egg hunting than experience anyway.

Final thoughts: No real issues on the lab at all.

1 comment:

Joni said...

hey. Been reading your posts for almost 6 months now. I have my own lab in october, SP also. I've gone through IE WP1 and iementor's small scenarios and all master labs and now I'm starting with IE WP2 but I ran into problem; Dynamips topology IE provides on their webpage does not match with the initial configuration files they also have available. Have you come across this same problem? As far as I understood, you're running labs on Dynamips instead of hardware also?

If you happen to have either a fixed topology file or fixed configuration files to match the topology, I'd be most delighted if you could share them with me.