Extend lab with Core, Campus fabric, and clean device naming #41

Damien · 2026-04-24T08:24:20Z

Damien commented

2026-04-24 08:24:20 +00:00

Summary

Extend the original DC-only topology with two new domains: a Core (AS 65500, iBGP, VRF-gold transit) and a full Campus EVPN-VXLAN fabric (spines, leaf pairs, border leafs, access, hosts)
Wire DC ⇄ Core ⇄ Campus so tenant VRFs reach end-to-end; VRF gold is the inter-fabric transit and hosts on either side can ping across
Rename every device to an <area>-<role> scheme (dc-spine, dc-leaf, dc-border-leaf, dc-access, dc-server, campus-border-leaf), leaving campus/core unchanged where already correct
Update annotations with a full set of AS group boxes (one per AS: 65000, 65001-4, 65005, 65500, 66000, 66001-2, 66005)
Refresh README, TROUBLESHOOTING, END_TO_END_TESTING and the SVG diagram to match the new topology and names

Test plan

clab deploy -t evpn-lab.clab.yml brings up all 34 nodes with the new names
DC server ↔ DC server ping inside each tenant VRF
Campus host ↔ Campus host ping inside VRF gold
Campus host ↔ DC server ping across Core (VRF gold transit)
Default route learned on campus hosts via fabric
BGP EVPN sessions up on every VTEP; Type-5 routes present for gold
Topology viewer renders the AS group boxes around the correct node pairs

## Summary - Extend the original DC-only topology with two new domains: a **Core** (AS 65500, iBGP, VRF-gold transit) and a full **Campus EVPN-VXLAN fabric** (spines, leaf pairs, border leafs, access, hosts) - Wire DC ⇄ Core ⇄ Campus so tenant VRFs reach end-to-end; VRF gold is the inter-fabric transit and hosts on either side can ping across - Rename every device to an `<area>-<role>` scheme (`dc-spine`, `dc-leaf`, `dc-border-leaf`, `dc-access`, `dc-server`, `campus-border-leaf`), leaving campus/core unchanged where already correct - Update annotations with a full set of AS group boxes (one per AS: 65000, 65001-4, 65005, 65500, 66000, 66001-2, 66005) - Refresh README, TROUBLESHOOTING, END_TO_END_TESTING and the SVG diagram to match the new topology and names ## Test plan - [x] `clab deploy -t evpn-lab.clab.yml` brings up all 34 nodes with the new names - [x] DC server ↔ DC server ping inside each tenant VRF - [x] Campus host ↔ Campus host ping inside VRF gold - [x] Campus host ↔ DC server ping across Core (VRF gold transit) - [x] Default route learned on campus hosts via fabric - [x] BGP EVPN sessions up on every VTEP; Type-5 routes present for gold - [x] Topology viewer renders the AS group boxes around the correct node pairs

Damien added 15 commits 2026-04-24 08:24:21 +00:00

Extend topology with Core, Campus fabric and DC Border Leafs 5e4b39d05d

Add node declarations and links for:
- DC Border Leaf MLAG pair (border-leaf-dc1/2)
- Core routers (core1, core2) interconnected via eth5
- Campus spines, leafs, border leafs, access switches and two hosts
- DC spine eth9/eth10 uplinks toward DC Border Leafs (underlay + EVPN)

Add DC Border Leaf configs (AS 65005, MLAG pair) d3b3c38ead

Both border leafs share VTEP Loopback1 10.0.255.15 and peer with DC
spines in eBGP IPv4 + EVPN. Uplinks to core1/core2 use dot1q
subinterfaces (.100 default underlay, .200 VRF gold) with OSPF area 0
and eBGP to AS 65500. VRF gold extended via vxlan vrf gold vni 100001
with RD <Lo0>:1 and RT 1:100001.

Add Core router configs (AS 65500, iBGP + VRF gold transit) 4b4c1852c4

core1/core2 provide L3 transit between DC and Campus fabrics. Each
physical link toward a Border Leaf is subinterfaced (.100 default,
.200 VRF gold). OSPF area 0 in default VRF, eBGP to DC BLs (65005)
and Campus BLs (66005), iBGP between core1 and core2 via Loopback0.
VRF gold uses redistribute connected and VRF-aware eBGP sessions on
.200 subinterfaces to stitch VRF gold end-to-end across fabrics.

Add Campus EVPN-VXLAN fabric configs and host interfaces 6e0dcce746

- campus-spine1/2 (AS 66000): eBGP underlay + EVPN RR toward leafs
  and border leafs, addressing plan 10.1.x.x.
- campus-leaf1/2 (VTEP1, AS 66001, VTEP 10.1.255.11): VLAN 50
  (stretched L2 VXLAN, VNI 110050) and VLAN 60 (VRF gold anycast
  10.60.60.1, L3 VNI 100001).
- campus-leaf3/4 (VTEP2, AS 66002, VTEP 10.1.255.12): VLAN 50 and
  VLAN 70 (VRF gold anycast 10.60.70.1).
- border-leaf-campus1/2 (AS 66005, VTEP 10.1.255.21): MLAG pair,
  OSPF + eBGP to cores, VRF gold stitched via vxlan vrf gold
  vni 100001 with RT 1:100001.
- campus-access1/2: L2-only uplinks to campus leaf MLAG pairs,
  trunks VLAN 50+60 / 50+70.
- campus-host1/2 interface files: bond0 + VLAN sub-interfaces for
  the stretched L2 VLAN 50 and the VRF gold subnets.

Update docs and diagram for extended multi-fabric topology ff15e90b5c

- README: rewritten node inventory, AS map, addressing plan
  (management, Lo0/Lo1, P2P, hosts), VNI/RD/RT tables, control-plane
  summary and end-to-end Campus <-> DC test procedures through the
  Core (VRF gold stitching).
- hosts/README: document the two new Campus host configurations.
- assets/arista-evpn-fabric.svg: new three-zone layout (Campus, Core,
  DC) with legend.
- evpn-lab.clab.yml.annotations.json: reposition nodes and add zone
  labels so the ContainerLab graph matches the extended topology.

Update campus host attachment pattern to single-attached access 2da238e3ae

Update cEOS version f7c44bc0fd

Fix VRF gold BGP IPv4 activation on cores and border leafs cb74dd118f

With 'no bgp default ipv4-unicast' set at the router level, VRF gold
eBGP/iBGP neighbors were establishing but not exchanging any IPv4
prefixes, breaking inter-fabric transit between DC and Campus. Add an
explicit 'address-family ipv4' block with 'neighbor X activate' under
'vrf gold' on both cores and all four border leafs.

Also drop 'redistribute learned' from the border leaf VRF gold stanza:
it is not a valid command in that context and was silently stripped by
EOS.

Force fabric default route on campus hosts 97fbc1cebe

The 'ip route add default via <fabric-gw>' exec command silently failed
on campus-host1 and campus-host2 because the management DHCP on eth0
had already installed a default via 172.16.0.254. As a result, traffic
leaving the host for other fabric subnets was sent out the management
interface instead of the EVPN fabric, breaking end-to-end ping.

Switch to 'ip route replace' so the fabric gateway overrides whatever
default is installed at container start.

Move campus host config into /etc/network/interfaces 46c68b42bd

Make hosts/campus-host{1,2}_interfaces the source of truth for the
campus host IP and default route, and have clab simply invoke 'ifup
eth1' at container start to apply it. Previously the bound interfaces
file was unused and the real config lived in the YAML exec block,
which was misleading.

BusyBox ifup in the network-multitool image needs 'address' plus
'netmask' rather than a CIDR, so split the address accordingly. Also
add 'post-up ip route replace default via <fabric-gw>' so the fabric
default overrides the management DHCP default even when one is already
installed.

Drop 'gateway' directive from campus host interfaces 8a725ab5fe

BusyBox ifup translates 'gateway X' into 'ip route add default via X'
and aborts the whole ifup run with RC=1 when that command fails with
'File exists' — which always happens on first boot because the docker
management bridge has already installed its own default via eth0. As a
result the 'post-up ip route replace default' was never executed and
the host kept the management default.

Remove the 'gateway' line so ifup only runs the idempotent 'post-up ip
route replace default via <fabric-gw>' and the fabric default wins.

Rename devices to <area>-<role> scheme ef4211afe5

DC fabric: spine/leaf/border-leaf/access/host -> dc-spine, dc-leaf,
dc-border-leaf, dc-access, dc-server. Campus border leafs flipped
from border-leaf-campus to campus-border-leaf for consistency. Core,
campus spines/leafs/access/hosts unchanged.

Updates topology, annotations, all configs (hostnames + peer
descriptions), host interface files, README, TROUBLESHOOTING,
END_TO_END_TESTING, and the SVG diagram.

Add AS group annotations for remaining fabrics ae4fd56635

Complete the AS group boxes: add AS65000 (dc-spines),
AS65002/3/4 (dc-leaf pairs), AS66000 (campus-spines),
AS66001/2 (campus-leaf pairs), AS66005 (campus-border-leaf).

Update documentation and annotation 9bb168abe1

Update arista cEOS image version bd3dbc181c

Damien added 1 commit 2026-04-24 08:24:41 +00:00

update annotation 2e57976c56

Damien merged commit baa95a33c0 into main

2026-04-24 08:25:17 +00:00

Damien referenced this issue from a commit

2026-04-24 08:25:19 +00:00

Merge pull request 'Extend lab with Core, Campus fabric, and clean device naming' (#41) from feat/extend-campus-core into main

Damien deleted branch feat/extend-campus-core

2026-04-24 08:25:21 +00:00

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