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Cumulus In The Cloud

Description Cumulus In The Cloud
Components Cumulus Linux
Resource requirements1 2
4 GB
Topology file symm-mh.clab.yml
Name cvx04
Version information2 cvx:4.3.0 docker-ce:19.03.13
Authors Michael Kashin


The lab is a multi-node topology that consists of two racks with two dual-homed servers connected with a leaf-spine network.

Use cases#

This is a "Cumulus In The Cloud" topology designed to demonstrate some of the advanced features of Cumulus Linux. It is based on the original CITC demo environment with the only exception being the reduced number of spine switches (2 instead of 4). The topology can be spun up fully provisioned with the following two configuration options:

  1. EVPN Multi-Homing -- an EVPN-VXLAN environment with layer 2 extension, layer 3 VXLAN routing and VRFs for multi-tenancy that uses a multicast underlay for VXLAN packet replication and does not use MLAG or CLAG.
  2. EVPN Symmetric Mode -- an EVPN-VXLAN environment with layer 2 extension, layer 3 VXLAN routing, VRFs for multi-tenancy and MLAG/CLAG for server multi-homing.


Each configuration option is provided in its own configuration file -- symm-mh.clab.yml or symm-mlag.clab.yml.

Once up, each node can be accessed via ssh using its hostname (automatically populated in your /etc/hosts file) and the default credentials root/root:

ssh root@clab-citc-leaf01
Warning: Permanently added 'clab-citc-leaf01,' (ECDSA) to the list of known hosts.
root@clab-citc-leaf01's password:
Linux 94992c82719f1172 4.19.0-cl-1-amd64 #1 SMP Cumulus 4.19.149-1+cl4.3u1 (2021-01-28) x86_64
Last login: Fri Jul  9 13:35:48 2021 from

  1. Resource requirements are provisional. Consult with the installation guides for additional information. 

  2. The lab has been validated using these versions of the required tools/components. Using versions other than stated might lead to a non-operational setup process.