Using an MRS Client for Nodes Outside a Cluster
After the client is prepared, users can use the client on a node outside the MRS cluster.
If the client has been installed on the node outside the MRS cluster but must be updated, update the client using the same account that is used to install the client, for example, the root account.
- An ECS has been prepared. For details about the OS and its version of the ECS, see Table 1.
Table 1 Reference list
- Recommended: SUSE Linux Enterprise Server 11 SP4 (SUSE 11.4)
- Available: SUSE Linux Enterprise Server 11 SP3 (SUSE 11.3)
- Available: SUSE Linux Enterprise Server 11 SP1 (SUSE 11.1)
- Available: SUSE Linux Enterprise Server 11 SP2 (SUSE 11.2)
- Recommended: Red Hat-6.6-x86_64 (Red Hat 6.6)
- Available: Red Hat-6.4-x86_64 (Red Hat 6.4)
- Available: Red Hat-6.5-x86_64 (Red Hat 6.5)
- Available: Red Hat-6.7-x86_64 (Red Hat 6.7)
- Available: CentOS-6.4 (CentOS 6.4)
- Available: CentOS-6.5 (CentOS 6.5)
- Available: CentOS-6.6 (CentOS 6.6)
- Available: CentOS-6.7 (CentOS 6.7)
- Available: CentOS-7.2 (CentOS 7.2)
For example, a user can select the image CentOS 7.2 64bit(40GB) to prepare the OS for an ECS.
In addition, sufficient disk space is allocated for the ECS, for example, 40 GB.
- The ECS and the MRS cluster are in the same VPC.
- The IP address configured for the NIC of the ECS is in the same network segment as the IP address of the MRS cluster.
- The security group of the ECS is the same as that of the Master node of the MRS cluster.
If this requirement is not met, modify the ECS security group or configure the inbound and outbound rules of the ECS security group to allow the ECS security group to be accessed by all security groups of MRS cluster nodes.
For details about how to create an ECS that meets this requirement, see "Creating an ECS" under the "Getting Started" chapter in the Elastic Cloud Server User Guide.
- To enable users to log in to a Linux ECS using a password (SSH), see "Logging In to a Linux ECS Using a Password (SSH)" in the Elastic Cloud Server User Guide (Getting Started > Logging In to an ECS > Logging In to a Linux ECS Using a Password (SSH)).
- Create an ECS that meets the requirements in the prerequisites.
- Log in to the MRS management console, click the cluster name to go to the cluster details page, and choose Components.
- If the Components tab is not displayed on the cluster details page, perform IAM user synchronization first. (On the Dashboard tab page of the cluster details page, click on the right side of IAM User Sync to synchronize IAM users.)
- For MRS 2.0.1 or earlier, log in to MRS Manager. For details, see Accessing MRS Manager. Then, choose Services.
- Click Download Client.
- In Client Type, select All client files.
- In Save Path, select Remote host.
- Set Host IP Address to the IP address of the ECS, set Host Port to 22, and set Save Path to /tmp.
- If the default port 22 for logging in to an ECS using SSH has been changed, set Host Port to the new port.
- Save Path contains a maximum of 256 characters.
- Set Login User to root.
If other users are used, ensure that they have read, write, and execute permission on the save path.
- Select Password or SSH Private Key in Login Mode.
- Password: Enter the password of user root set during cluster creation.
- SSH Private Key: Select and upload the key file used for creating the cluster.
- Click OK to start downloading the client to the ECS.
If the following information is displayed, the client package is successfully saved. Click Close.
Client files downloaded to the remote host successfully.
If the following information is displayed, check the username, password, and security group configurations of the remote host. Ensure that the username and password are correct and an inbound rule of the SSH(22) port has been added to the security group of the remote host. And then, go to 2 to download the client again.
Failed to connect to the server. Please check the network connection or parameter settings.
Generating a client will occupy a large number of disk I/Os. You are advised not to download a client when the cluster is being installed, started, and patched, or in other unstable states.
- Log in to the ECS using VNC. See "Logging In to a Linux ECS Using VNC" in the Elastic Cloud Server User Guide (Getting Started > Logging In to an ECS > Logging In to a Linux ECS Using VNC).
All images support Cloud-Init. The preset username for Cloud-init is root and the password is the one you set during cluster creation. It is recommended that you change the password upon the first login.
- On the ECS, switch to user root and copy the installation package to the /opt directory.
sudo su - root
cp /tmp/MRS_Services_Client.tar /opt
- Run the following command in the /opt directory to decompress the package and obtain the verification file and the configuration package of the client:
tar -xvf MRS_Services_Client.tar
- Run the following command to verify the configuration package of the client:
sha256sum -c MRS_Services_ClientConfig.tar.sha256
The command output is as follows:
- Run the following command to decompress MRS_Services_ClientConfig.tar:
tar -xvf MRS_Services_ClientConfig.tar
- Run the following command to install the client to a new directory, for example, /opt/client. A directory is automatically generated during installation.
sh /opt/MRS_Services_ClientConfig/install.sh /opt/client
If the following information is displayed, the client is successfully installed:
Components client installation is complete.
- Check whether the IP address of the ECS node is connected to the IP address of the cluster Master node.
For example, run the following command: ping Master node IP address.
- Run the following command to configure the environment variable:
- If the Kerberos authentication is enabled for the current cluster, run the following command to authenticate the user. If the Kerberos authentication is disabled for the current cluster, skip this step.
kinit MRS cluster user
For example, kinit admin.
- Run the client command of the component.
For example, run the following command to query the HDFS directory.
hdfs dfs -ls /