E-MapReduce:Create an SSH tunnel to access the web UIs of open source components

Connect to the master node by using a key

ssh -i <Key file path> -N -L <Local port>:<Name of the master node>:<Component port> root@<Public IP address of the master node>

Parameter description:

• -i: the path of the private key file used for identity authentication.

• -N: used only to enable port forwarding and create an SSH tunnel without the need to run commands.

• -L: Local port forwarding is enabled. You can specify a local port to forward data to the remote port hosted on your on-premises web server of the master node.

• <Key file path>: the path in which the key file is stored. For more information, see Manage SSH key pairs.

• <Local port>: You can use an unoccupied port on your on-premises server. Example: 8156.

• <Name of the master node>: the name of the master node. You can view the name on the Nodes tab of the cluster. Example: master-1-1. For more information, see Obtain the public IP address and the name of a node.

• <Component port>: the port of an open source component. For more information about component ports, see Common ports of open source components. Example: 8088.

• <Public IP address of the master node>: the public IP address of the master node. You can view the address on the Nodes tab of the cluster. For more information, see Obtain the public IP address and the name of a node.

Connect to the master node by using a username and password

ssh -N -L <Local port>:<Name of the master node>:<Component port> root@<Public IP address of the master node>

Parameter description:

• -N: used only to enable port forwarding and create an SSH tunnel without the need to run commands.

• -L: Local port forwarding is enabled. You can specify a local port to forward data to the remote port hosted on your on-premises web server of the master node.

• <Local port>: You can use an unoccupied port on your on-premises server. Example: 8156.

• <Name of the master node>: the name of the master node. You can view the name on the Nodes tab of the cluster. Example: master-1-1. For more information, see Obtain the public IP address and the name of a node.

• <Component port>: the port of an open source component. For more information about component ports, see Common ports of open source components. Example: 8088.

• <Public IP address of the master node>: the public IP address of the master node. You can view the address on the Nodes tab of the cluster. For more information, see Obtain the public IP address and the name of a node.

Connect to the master node by using a key

ssh -i <Key file path> -N -D <Port> root@<Public IP address of the master node>

Parameter description:

• -i: the path of the private key file used for identity authentication.

• -N: used only to enable port forwarding and create an SSH tunnel without the need to run commands.

• -D: Dynamic port forwarding is enabled. Start the SOCKS proxy process to listen on the port.

• <Key file path>: the path in which the key file is stored. For more information, see Manage SSH key pairs.

• <Local port>: You can use an unoccupied port on your on-premises server. Example: 8157.

• <Public IP address of the master node>: the public IP address of the master node. You can view the address on the Nodes tab of the cluster. For more information, see Obtain the public IP address and the name of a node.

Connect to the master node by using a username and password

ssh -N -D <Local port> root@<Public IP address of the master node>

Parameter description:

• -N: used only to enable port forwarding and create an SSH tunnel without the need to run commands.

• -D: Dynamic port forwarding is enabled. Start the SOCKS proxy process to listen on the port.

• <Local port>: You can use an unoccupied port on your on-premises server. Example: 8157.

• <Public IP address of the master node>: the public IP address of the master node. You can view the address on the Nodes tab of the cluster. For more information, see Obtain the public IP address and the name of a node.

Use the CLI

1. Open the CLI on your on-premises machine and go to the installation directory of the Google Chrome browser client.

   Operating system	Default installation directory of Google Chrome
   macOS X	/Applications/Google\ Chrome.app/Contents/macOS
   Linux	/usr/bin/google-chrome
   Windows	Default installation directories of Google Chrome for 64-bit and 32-bit systems: C:\Program Files\Google\Chrome\Application\ C:\Program Files (x86)\Google\Chrome\Application\

   Note

   The default installation directory of Google Chrome varies based on the operating system.

2. Configure Google Chrome to use a local SOCKS proxy and start the Google Chrome browser. Use the port that you enabled when you create an SSH tunnel in Step 1.

   Note

   In this example, Port 8157 is used.

   macOS X

   ./Google\ Chrome --proxy-server="socks5://localhost:8157" --host-resolver-rules="MAP * 0.0.0.0 , EXCLUDE localhost" --user-data-dir=/tmp/

   Linux

   chrome --proxy-server="socks5://localhost:8157" --host-resolver-rules="MAP * 0.0.0.0 , EXCLUDE localhost" --user-data-dir=/tmp/

   Windows

   chrome --proxy-server="socks5://localhost:8157" --host-resolver-rules="MAP * 0.0.0.0 , EXCLUDE localhost" --user-data-dir=c:\\tmppath\\

Use a Google Chrome extension

Extensions allow you to easily manage and use proxies in your web browser. You can use an extension to browse web pages and access web UIs at the same time.

1. Add the Google Chrome extension SwitchyOmega.

2. On the SwitchyOmega page, click New profile in the left-side navigation pane. In the New Profile dialog box, enter a profile name, such as SSH tunnel, in the Profile name field, select PAC Profile, and then click Create.

3. Enter the following content in the PAC Script editor:

   Note

   In this example, Port 8157 is used.

   function regExpMatch(url, pattern) {
     try {
       return new RegExp(pattern).test(url);
     } catch (ex) {
       return false;
     }
   }
   
   function FindProxyForURL(url, host) {
     if (shExpMatch(url, "*localhost*")) return "SOCKS5 localhost:8157";
     if (shExpMatch(url, "*emr-header*")) return "SOCKS5 localhost:8157";
     if (shExpMatch(url, "*emr-worker*")) return "SOCKS5 localhost:8157";
     if (shExpMatch(url, "*master*")) return "SOCKS5 localhost:8157";
     if (shExpMatch(url, "*core*")) return "SOCKS5 localhost:8157";
     return 'DIRECT';
   }

4. In the left-side navigation pane, click Apply changes to complete the configuration.

5. In the upper-right corner of the browser, select the SSH tunnel that you created.