Lab Topology Reference¶
The lab topology is described in a YAML file using a dictionary format. You could use hierarchical attribute names as dictionary keys to make the topology file more readable.
The three major components that should be present in every topology file are:
nodes – lab devices (nodes)
links – links between the lab devices
defaults – topology-wide defaults like default device type
Other topology elements include:
addressing – IPv4 and IPv6 pools used to address management, loopback, LAN, P2P and stub interfaces
components – reusable components that you can include in multiple places in the lab topology
groups – optional groups of nodes
module – default list of modules used by this network topology. You can use device-level module attribute to override this setting for individual nodes.
plugin – list of plugins used by this topology.
tools – dictionary of external network management tools deployed after the lab has been started and configured.
validate – lab validation tests
Finally, you can set these topology-level parameters:
provider – virtualization provider (default: libvirt)
name – topology name (used in bridge names)
version – minimum netlab version required to use this lab topology. You can use either a simple version number or Python module version specification (example:
>= 1.6.3). See Version-Specific Lab Topology Files for more details.
All elements apart from nodes are optional – missing links element indicates a topology without inter-node links (just the management interfaces)
Default values of defaults and addressing elements are taken from default settings.
List of modules is used to specify additional initial configuration elements (example: OSPF routing)
Default topology name is the directory name.
You’ll find sample topology files in the tutorials.
- Nodes (Network Devices)
- Links between Network Devices
- Groups of Lab Devices (Nodes)
- Topology Address Pools
- Optional Configuration Modules
- Custom Configuration Templates
- Integrating External Tools
- netlab Plugins
- Virtualization Providers
- Topology Components
- Topology Defaults
- Hierarchical Dictionaries in netlab YAML files
- Lab Validation Tests
- Customize netlab