Cisco vIOS#

Cisco vIOS virtualized router/switch is identified with cisco_vios kind in the topology file. It is built using vrnetlab project and essentially is a Qemu VM packaged in a docker container format.

The cisco_vios kind supports both router (vIOS) and Layer 2 switch (vIOSL2) images. The type is specified using the type parameter in the node configuration.

Node Types#

The cisco_vios kind supports two node types:

• router (default) - Cisco vIOS router image
• switch - Cisco vIOSL2 Layer 2 switch image

The node type is specified using the type parameter:

topology:
  nodes:
    router1:
      kind: cisco_vios
      type: router  # or omit for default router type
      image: vrnetlab/cisco_vios:159-3.M10

    switch1:
      kind: cisco_vios
      type: switch
      image: vrnetlab/cisco_vios:L2-20200929

Managing Cisco vIOS nodes#

Cisco vIOS node launched with containerlab can be managed via the following interfaces:

docker exec -it <container-name/id> bash

ssh admin@<container-name/id>

Interface naming#

You can use interfaces names in the topology file like they appear in Cisco vIOS.

The interface naming convention is: GigabitEthernetX (or GiX), where X is the port number.

With that naming convention in mind:

• Gi0 - first data port available
• Gi1 - second data port, and so on...

The example ports above would be mapped to the following Linux interfaces inside the container running the Cisco vIOS VM:

• eth0 - management interface connected to the containerlab management network (rendered as GigabitEthernet0/0 in the CLI)
• eth1 - first data interface, mapped to the first data port of the VM (rendered as GigabitEthernet0)
• eth2+ - second and subsequent data interfaces, mapped to the second and subsequent data ports of the VM (rendered as GigabitEthernet1 and so on)

When containerlab launches Cisco vIOS node the management interface gets assigned an address from the containerlab management network.

Data interfaces GigabitEthernet0+ need to be configured with IP addressing manually using CLI or other available management interfaces.

Features and options#

Node configuration#

Cisco vIOS nodes come up with a basic configuration where only admin user and management interface are provisioned.

Startup configuration#

It is possible to make vIOS nodes boot up with a user-defined startup-config instead of a built-in one. With a startup-config property of the node/kind user sets the path to the config file that will be mounted to a container and used as a startup-config:

topology:
  nodes:
    node:
      kind: cisco_vios
      startup-config: myconfig.txt

With this knob containerlab is instructed to take a file myconfig.txt from the directory that hosts the topology file, and copy it to the lab directory for that specific node under the /config/startup-config.cfg name. Then the directory that hosts the startup-config dir is mounted to the container. This will result in this config being applied at startup by the node.

Configuration is applied after the node is started, thus it can contain partial configuration snippets that you desire to add on top of the default config that a node boots up with.