Host

A node of kind host represents the containerlab host the labs are running on. It is a special node that is implicitly used when nodes have links connected to the host - see host links.

But there is a use case when users might want to define the node of kind host explicitly in the topology. For example, when some commands need to be executed on the host for the lab to function.

In such case, the following topology definition can be used:

h1:
  kind: host
  exec:
    - ip link set dev enp0s3 up

In the above example, the node h1 is defined as a node of kind host and the exec option is used to run the command ip link set dev enp0s3 up in the containerlab host. Of course, the command can be any other command that is required for the lab to function.