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NetLab

Network topology simulation service. Creates and manages simulated network topologies for testing network configurations, routing behavior, and distributed system interactions in isolated environments.

Routes

The netlab-hosted/ route runs the manager (netlab-manager-server.jar, started with --worker-jar-path /root/ContainerNursery/apps/netlab-worker-server.jar); the manager uploads that worker jar to each on-demand droplet it provisions. Both jars live under /root/ContainerNursery/apps/. Deployed versions (2026-06-13): manager netlabmanager:netlab-manager-server:0.0.30, worker netlabserviceserver:netlab-service-server:0.0.24.

Architecture

          +---------------------------+
          |         Clients           |
          +---------------------------+
                |             |
          url://|             | url://
                v             v
   +----------------------+ +----------------------+
   | netlab-service-      | | netlab-worker-       |
   |    server.jar        | |    server.jar        |
   | (ContainerNursery)   | | (ContainerNursery)   |
   | url://netlab/        | | url://netlab-hosted/ |
   +----------------------+ +----------------------+
                |             |
                v             v
          +---------------------------+
          |  Topology Simulation      |
          |       Engine              |
          +---------------------------+
                      |
                      v
          +---------------------------+
          |   Network State Store     |
          +---------------------------+

Dependents

• Services and developers requiring simulated network topologies for testing

Deployment

• ContainerNursery: netlab-service-server.jar deployed to ContainerNursery, accessible via url://netlab/. netlab-worker-server.jar deployed to ContainerNursery, accessible via url://netlab-hosted/.

Health Checks

• ContainerNursery: both services monitored via standard ContainerNursery health checks

Notes

• Standard layered architecture with a service layer and a worker layer.
• The service server manages topology definitions and orchestrates simulations.
• The worker server executes hosted simulation workloads.
• Both endpoints are internal ContainerNursery services with no public HTTPS routes.
• Real-internet isolation: topologies provisioned through netlab-hosted/ are isolated from the real internet — the deployed worker (netlab-service-server:0.0.24) creates switches as Docker --internal networks, attaches networkless hosts to --network none, rejects "internal": false, and grants outbound access only through an explicit internet_gateways node. See the NetLab project overview. Redeploying the manager with a newer worker jar (--worker-jar-path) is what rolls this enforcement out to newly-provisioned droplets.