As always, this tutorial will be backed up by a lab that readers can effortlessly deploy on their machine and follow along. Oper-group lab is contained within srl-labs/oper-group-lab repository and features:
- A Clos based fabric with 4 leaves and 2 spines, forming the fabric
- Two dual-homed clients emulated with linux containers and running
iperfsoftware to generate traffic
- L2 EVPN service1 configured across the leaves of the fabric
- A telemetry stack to demonstrate oper-group operations in action.
On a physical layer topology interconnections are layed down as follows:
Each client is dual-homed to corresponding leaves; To achieve that, interfaces
eth2 are formed into a
On the leaves side, the access interface `Ethernet-1/1`` is part of a LAG interface that is "stretched" between a pair of leaves, forming a logical construct similar to MC-LAG.
In the underlay of a fabric leaves and spines run eBGP protocol to enable leaves to exchange reachability information for their
eBGP peerings are formed between each leaf and spine pair.
To support BGP EVPN service, in the overlay iBGP peerings with EVPN address family are established from each leaf to each spine, with spines acting as route reflectors.
From the EVPN service standpoint, the mac-vrf instance named
vrf-1 is created on leaves and
ES-1 ethernet segment is formed from a LAG interface.
Ethernet segments are configured to be in an all-active mode to make sure that every access link is utilized in the fabric.
We have enhanced the lab with a telemetry stack featuring gnmic, prometheus, and grafana - our famous GPG stack. Nothing beats real-time visualization, especially when we want to correlate events happening in the network.
Start with cloning lab's repository
Lab repository contains startup configuration files for the fabric nodes, as well as necessary files for the telemetry stack to come up online operational. To deploy the lab:
This will stand up a lab with an already pre-configured fabric using startup configs contained within
The deployed lab starts up in a pre-provisioned step, where underlay/overlay configuration has already been done. We proceed with oper-group use case exploration in the next chapter of this tutorial.