Ethernet Services

Lab file

77KB

Challenge - Ethernet Services.yaml

Startup configs

31KB

ethernet_services_initial_configs.zip

archive

IP addressing, IGP, and Segment Routing are pre-configured.

1. Create an E-Access service connecting CUSTOMER1_R1 and CUSTOMER1_R2. The two service providers agree to use vlan 384 for this service. The customer routers already have OSPF pre-configured, so they should achieve an OSPF adjacency once the service is setup correctly. The PEs should allow frames from the customer with any tag.

The customer routers should be able to ping each other on their loopbacks.

CUSTOMER1_R1#ping 2.2.2.2 source 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2.2.2.2, timeout is 2 seconds:
Packet sent with a source address of 1.1.1.1 
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 5/11/22 ms

2. Create an E-LAN service for CUSTOMER2 within service provider 1. These customer routers have ISIS pre-configured. They should achieve full ISIS adjacencies on this broadcast segment. As a challenge try to configure this two different ways, one with explicit neighbors and one with auto-discovery.

You should see two adajacencies with each router (one L1 and one L2, because ISIS is L1-L2 by default).

CUSTOMER2_R1#show isis nei

System Id       Type Interface     IP Address      State Holdtime Circuit Id
CUSTOMER2_R2    L1   Gi1           10.0.0.2        UP    29       CUSTOMER2_R1.01    
CUSTOMER2_R2    L2   Gi1           10.0.0.2        UP    27       CUSTOMER2_R1.01    
CUSTOMER2_R3    L1   Gi1           10.0.0.3        UP    29       CUSTOMER2_R1.01    
CUSTOMER2_R3    L2   Gi1           10.0.0.3        UP    29       CUSTOMER2_R1.01

Answers

E-Access

For the E-Access service, you must create two separate E-Line services. One xconnect from SP1_R1 to SP1_R4, and one from SP2_XR1 to SP2_XR2. Gi2 on SP1_R4 should match dot1q 384 and pop the tag on ingress. Same for SP2_XR1 on Gi0/0/0/1. SP1_R1 Gi2 should use encapsulation default to allow any tag. On SP2_XR2, you can simply leave the port in l2transport mode.

In order for targeted LDP to work for the pseudowires, you need to accept targeted hellos on all four routers. By default, IOS-XE appears to accept LDP neighborships with no configuration, but on IOS-XR you must enable mpls ldp.

E-LAN

For the E-LAN service, you will also need to accept targeted LDP hellos on SP1_R2. You will create an l2vpn vfi, specify the neighbors (in this case only two PEs total), and add the vfi and interfaces to a bridge domain.

The tricky aspect of this lab is that ISIS is used on the customer network. ISIS pads the hello as an MTU check. You’ll find that R2 and R3 form an adjacency, but R1 forms no adjacencies. This is because the padded ISIS hello plus the MPLS label and control word is too large. The service provider 1 network has all interfaces with the default MTU. You will need to increase MTU to 1526 (1500 + 14 (ethernet header) + 8 (MPLS labels) + 4 (control word)).

To enable autodiscovery you need to run BGP with l2vpn vpls AFI. As a shortcut you can techinically run BGP only on SP1_R1 and SP1_R2. Then change the vfi defintion to use autodiscovery.