Connect to a Cluster Node Through Secure Shell (SSH)

To gain local access to the tools, utilities and other resources on anOracle Big Data Cloud Service cluster node, use Secure Shell (SSH) client software to establish a secure connection and log in.

Note:

By default, the port used for accessing the cluster through SSH, port 22, is open. You can control access to that and other ports by configuring the network whitelist (for clusters hosted in regions) or by configuring the firewall (for cluster hosted in availability domains). The configuration controls whether network requests from specified IP addresses (or ranges of addresses) will be accepted or denied at specified ports. See Control Network Access to Services.

Several SSH clients are freely available. The following sections show how to use SSH clients on UNIX, UNIX-like, and Windows platforms to connect to a node.

The following instructions describe how to connect as the opc user and then use the sudo command to open a root shell. After you do this the first time, you may choose instead to connect using a password by assigning a known password to opc or creating another user with a known password.

Connecting to a Node By Using PuTTY on Windows

PuTTY is a freely available SSH client program for Windows.

Before You Begin

Before you use the PuTTY program to connect to a node, you need the following:

The IP address of the node

The IP address of the node is listed on the Cluster Details page for the cluster containing the node. To display this page, see View Details About a Cluster.
The SSH private key file that pairs with the public key associated with the cluster

The public key was associated with your cluster when it was created. See Create a Cluster. If you don’t have the private key that’s paired with the public key, contact your administrator.

The private key file must of the PuTTY .ppk format. If the private key file was originally created on the Linux platform, you can use the PuTTYgen program to convert it to the .ppk format.

For instructions on creating an SSH key pair, see Generating a Secure Shell (SSH) Public/Private Key Pair.

Procedure

To connect to a node using the PuTTY program on Windows:

Download and install PuTTY.

To download PuTTY, go to http://www.putty.org/ and click the You can download PuTTY here link.
Run the PuTTY program.

The PuTTY Configuration window is displayed, showing the Session panel.
In Host Name (or IP address) box, enter the IP address of the node.
Confirm that the Connection type option is set to SSH.
In the Category tree, expand Connection if necessary and then click Data.

The Data panel is displayed.
In the Auto-login username box, enter opc. As the opc user, you can use the sudo command to gain root access to the node, as described in the last step, below.
Confirm that the When username is not specified option is set to Prompt.
In the Category tree, expand SSH and then click Auth.

The Auth panel is displayed.
Click the Browse button next to the Private key file for authentication box. Then, in the Select private key file window, navigate to and open the private key file that matches the public key that is associated with the cluster.
In the Category tree, click Session.

The Session panel is displayed.
In the Saved Sessions box, enter a name for this connection configuration. Then, click Save.
Click Open to open the connection.

The PuTTY Configuration window is closed and the PuTTY window is displayed.

If this is the first time you are connecting to the VM, the PuTTY Security Alert window is displayed, prompting you to confirm the public key. Click Yes to continue connecting.
To perform operations that require root access to the node—such as issuing bda—ossadmin commands—open a root command shell. Enter sudo -s at the command prompt:
```
$ sudo -s
# whoami 
# root
```

Connecting to a Node By Using SSH on UNIX

UNIX and UNIX-like platforms (including Solaris and Linux) include the ssh utility, an SSH client.

Before You Begin

Before you use the ssh utility to connect to a node, you need the following:

The IP address of the node

The IP address of the node is listed on the Cluster Details page of the cluster containing the node. To display this page, see View Details About a Cluster.
The SSH private key file that pairs with the public key associated with the cluster

The public key was associated with your cluster when it was created. See Create a Cluster. If you don’t have the private key that’s paired with the public key, contact your administrator.

Procedure

To connect to a node using the ssh utility on UNIX and UNIX-like platforms:

In a command shell, set the file permissions of the private key file so that only you have access to it:
```
$ chmod 600 private-key-file
```
private-key-file is the path to the SSH private key file that matches the public key that is associated with the cluster.
Run the ssh utility:
```
$ ssh -i private-key-file opc@node-ip-address
```
where:
- private-key-file is the path to the SSH private key file.
- opc is the opc operating system user. As opc, you can use the sudo command to gain root access to the node, as described in the next step.
- node-ip-address is the IP address of the node in x.x.x.x format.
If this is the first time you are connecting to the node, the ssh utility prompts you to confirm the public key. In response to the prompt, enter yes.
To perform operations that require root access to the node—such as issuing bda-oss-admin commands—open a root command shell. Enter sudo -s at the command prompt:
```
$ sudo -s
# whoami 
# root
```