  graph TB

  Node1 -- interactive --> SubGraph2Flow
  Node1 -- sbatch --> SubGraph2Flow
  subgraph "Snowy"
  SubGraph2Flow(calculation nodes) 
        end

        ThinLinc -- usr-sensXXX + 2FA + VPN ----> SubGraph1Flow
        Terminal/ThinLinc -- usr --> Node1
        Terminal -- usr-sensXXX + 2FA + VPN ----> SubGraph1Flow
        Node1 -- usr-sensXXX + 2FA + no VPN ----> SubGraph1Flow
        
        subgraph "Bianca"
        SubGraph1Flow(Bianca login) -- usr+passwd --> private(private cluster)
        private -- interactive --> calcB(calculation nodes)
        private -- sbatch --> calcB
        end

        subgraph "Rackham"
        Node1[Login] -- interactive --> Node2[calculation nodes]
        Node1 -- sbatch --> Node2
        end
