Using a non-standard SSH port

Issue

Neutree connects to nodes via SSH to manage static node clusters. The default SSH port is 22. If your nodes use a different port, adding nodes may fail.

Solution

Neutree uses Ray as the underlying cluster management tool and does not support directly configuring the SSH port. In addition to being used for SSH connections, the head_ip and worker_ips values in the cluster configuration are also used as the Ray cluster GCS address (<head_ip>:6379) and Dashboard access address (http://<head_ip>:8265). Use an SSH configuration file to override the non-standard SSH port for node IP addresses.

Steps

1. Create an SSH configuration file and add port configuration for each node IP address.

   mkdir -p ./ssh-config
   cat > ./ssh-config/config << 'EOF'
   Host <host_ip>
       Port <ssh_port>
   EOF
   chmod 600 ./ssh-config/config

   Parameter descriptions:

   Parameter	Description
   Host <host_ip>	Node IP address. It must be the same as the head_ip and worker_ips values in the cluster configuration. Wildcards are supported. If multiple nodes use the same port, you can use a simplified form such as Host 192.168.1.*.
   Port <ssh_port>	SSH port used by the node.

   Information:

   • When Neutree connects to a node, it runs ssh <ssh_user>@<host_ip>. The Host entry in the SSH configuration must match the node IP address.
   • Neutree provides the username and key through the ssh_user and ssh_private_key values in the cluster configuration.

   Example

   mkdir -p ./ssh-config
   cat > ./ssh-config/config << 'EOF'
   Host 192.168.1.100
       Port 2222
   
   Host 192.168.1.101
       Port 2222
   EOF
   chmod 600 ./ssh-config/config

   This example creates ./ssh-config/config and adds the following configuration: nodes whose IP addresses are 192.168.1.100 and 192.168.1.101 use SSH port 2222.

2. Mount the SSH configuration file to the Neutree’s neutree-core container.

   Choose the appropriate method based on your deployment mode.

   Docker Compose

   1. Update the docker-compose.yaml file to mount the SSH configuration file to the neutree-core container.

      services:
        neutree-core:
          # ... other configurations
          volumes:
            - ./ssh-config:/root/.ssh:ro

   2. Restart the service.

      docker-compose up -d

   Note:

   When upgrading the Neutree control plane using docker-compose.yaml in the future, your custom volume mounts may be overwritten. After each upgrade, be sure to remount the SSH configuration file to the neutree-core container.

   Kubernetes

   1. Create a ConfigMap containing the SSH configuration.

      kubectl create configmap ssh-config --from-file=config=./ssh-config/config -n neutree

      Or create the ConfigMap using a YAML file:

      apiVersion: v1
      kind: ConfigMap
      metadata:
        name: ssh-config
        namespace: neutree
      data:
        config: |
          Host 192.168.1.100
              Port 2222

   2. Update the neutree-core Deployment to mount the SSH configuration file.

      apiVersion: apps/v1
      kind: Deployment
      metadata:
        name: neutree-core
        namespace: neutree
      spec:
        template:
          spec:
            containers:
              - name: neutree-core
                # ... other configurations
                volumeMounts:
                  - name: ssh-config
                    mountPath: /root/.ssh
                    readOnly: true
            volumes:
              - name: ssh-config
                configMap:
                  name: ssh-config
                  defaultMode: 0600

   3. Apply the configuration:

      kubectl apply -f neutree-core-deployment.yaml -n neutree

3. Test whether the SSH connection to the node is normal to verify that the SSH configuration file and node configuration are correct.

   You can run the following command on the host where Neutree is located to check whether the node port is reachable:

   nc -zv 192.168.1.100 2222

   Or, after adding the node to Neutree, check whether the cluster enters the Ready state.

4. Add nodes to the cluster in Neutree. For head_ip and worker_ips, enter node IP addresses.

Related links

For Ray-related limitations, see Ray Discuss: Specify SSH port to cluster YAMLs.