Topology Configuration#

The Topology custom resource (CR) is the primary way to deploy containerlab topologies in Kubernetes. This page covers all available configuration options.

Definition#

The definition field contains the containerlab topology in YAML format:

apiVersion: clabernetes.containerlab.dev/v1alpha1
kind: Topology
metadata:
  name: my-lab
spec:
  definition:
    containerlab: |
      name: my-lab
      topology:
        nodes:
          srl1:
            kind: nokia_srlinux
            image: ghcr.io/nokia/srlinux:latest

Expose Configuration#

Controls how topology nodes are exposed via Kubernetes Services.

Field	Type	Default	Description
`expose.exposeType`	enum	`LoadBalancer`	Service type: `LoadBalancer`, `ClusterIP`, `Headless`, or `None`
`expose.disableExpose`	bool	`false`	Disable all service creation
`expose.disableAutoExpose`	bool	`false`	Only expose ports explicitly defined in topology

Expose Types#

LoadBalancer: External IP via cloud load balancer or MetalLB
ClusterIP: Internal cluster access only
Headless: Direct pod DNS resolution (no kube-proxy)
None: No services created

Auto-Exposed Ports#

When disableAutoExpose: false (default), the following ports are automatically exposed:

Protocol	Ports
TCP	21, 22, 23, 80, 443, 830, 5000, 5900, 6030, 9339, 9340, 9559, 57400
UDP	161

Example#

spec:
  expose:
    exposeType: ClusterIP
    disableAutoExpose: true

Deployment Configuration#

Controls launcher pod settings.

Resources#

Per-node CPU and memory requirements:

spec:
  deployment:
    resources:
      default:  # Applied to all nodes
        requests:
          memory: "2Gi"
          cpu: "1"
        limits:
          memory: "4Gi"
          cpu: "2"
      srl1:  # Override for specific node
        requests:
          memory: "4Gi"
          cpu: "2"

Scheduling#

Node placement constraints using node selectors and tolerations:

spec:
  deployment:
    scheduling:
      nodeSelector:
        kubernetes.io/arch: amd64
        node-type: network-lab
      tolerations:
        - key: "dedicated"
          operator: "Equal"
          value: "network-lab"
          effect: "NoSchedule"

File Mounting#

Mount files from ConfigMaps or URLs into launcher pods.

From ConfigMap#

spec:
  deployment:
    filesFromConfigMap:
      srl1:
        - filePath: /opt/srlinux/etc/license.key
          configMapName: srl-license
          configMapPath: license.key
          mode: read  # or "execute"

From URL#

spec:
  deployment:
    filesFromURL:
      srl1:
        - filePath: /tmp/config.json
          url: https://example.com/config.json

Persistence#

Enable persistent storage across pod restarts:

spec:
  deployment:
    persistence:
      enabled: true
      claimSize: "10Gi"
      storageClassName: "fast-ssd"

Note

PVC size cannot be reduced after creation. Storage class is immutable after creation.

Other Deployment Options#

Field	Type	Default	Description
`deployment.privilegedLauncher`	bool	`true`	Run launcher in privileged mode
`deployment.containerlabDebug`	bool	`false`	Enable containerlab debug logging
`deployment.containerlabTimeout`	string	-	Deploy timeout (e.g., "30m")
`deployment.containerlabVersion`	string	-	Override containerlab version
`deployment.launcherImage`	string	-	Override launcher image
`deployment.launcherImagePullPolicy`	enum	-	Image pull policy: IfNotPresent, Always, Never
`deployment.launcherLogLevel`	enum	-	Log level: disabled, critical, warn, info, debug
`deployment.extraEnv`	list	-	Additional environment variables

Status Probes#

Health checking for containerlab nodes using SSH or TCP probes.

spec:
  statusProbes:
    enabled: true
    excludedNodes:
      - linux-host
    probeConfiguration:
      startupSeconds: 900
      sshProbeConfiguration:
        username: admin
        password: NokiaSrl1!
        port: 22
    nodeProbeConfigurations:
      router1:
        tcpProbeConfiguration:
          port: 830

Field	Description
`enabled`	Enable/disable status probes
`excludedNodes`	Nodes to exclude from probing
`probeConfiguration`	Default probe config for all nodes
`nodeProbeConfigurations`	Per-node probe overrides
`startupSeconds`	Total seconds allowed for node startup

Image Pull Configuration#

Control image pulling behavior:

spec:
  imagePull:
    pullThroughOverride: auto
    insecureRegistries:
      - internal-registry.local:5000
    pullSecrets:
      - my-registry-secret
    dockerDaemonConfig: daemon-config-secret
    dockerConfig: docker-config-secret

Field	Type	Description
`pullThroughOverride`	enum	Pull-through mode: auto, always, never
`insecureRegistries`	list	Registries without valid TLS
`pullSecrets`	list	Kubernetes secrets for private registries
`dockerDaemonConfig`	string	Secret with daemon.json
`dockerConfig`	string	Secret with Docker config.json

Connectivity#

Inter-node tunnel type for datapath stitching:

Value	Description
`vxlan`	VXLAN tunnels (default)
`slurpeeth`	Experimental TCP tunnels (avoids MTU issues)

spec:
  connectivity: vxlan

Naming#

Resource naming convention (immutable after creation):

Value	Description
`prefixed`	Include topology name in resource names
`non-prefixed`	No topology prefix (use separate namespaces)
`global`	Defer to global Config CRD

spec:
  naming: prefixed

Complete Example#

apiVersion: clabernetes.containerlab.dev/v1alpha1
kind: Topology
metadata:
  name: production-lab
spec:
  expose:
    exposeType: LoadBalancer
    disableAutoExpose: false
  deployment:
    resources:
      default:
        requests:
          memory: "4Gi"
          cpu: "2"
      core-router:
        requests:
          memory: "16Gi"
          cpu: "8"
    scheduling:
      nodeSelector:
        node-type: network-lab
    persistence:
      enabled: true
      claimSize: "20Gi"
    filesFromConfigMap:
      srl1:
        - filePath: /opt/srlinux/etc/license.key
          configMapName: srl-license
          configMapPath: license.key
    privilegedLauncher: true
    launcherLogLevel: info
  statusProbes:
    enabled: true
    probeConfiguration:
      startupSeconds: 900
      sshProbeConfiguration:
        username: admin
        password: NokiaSrl1!
  imagePull:
    pullThroughOverride: auto
  naming: prefixed
  connectivity: vxlan
  definition:
    containerlab: |
      name: production
      topology:
        nodes:
          core-router:
            kind: nokia_srlinux
            image: ghcr.io/nokia/srlinux:latest
          edge1:
            kind: nokia_srlinux
            image: ghcr.io/nokia/srlinux:latest
        links:
          - endpoints: ["core-router:e1-1", "edge1:e1-1"]

Nokia SR-SIM Support#

Clabernetes supports Nokia SR-SIM deployments, including distributed chassis systems (SR-7, SR-14s, etc.). For distributed systems using network-mode: container:<primary>, clabernetes automatically groups all cards into a single pod.