Elastic High Performance Computing:Manually scale out an E-HPC cluster

Prerequisites

• A vSwitch is configured in the region of the compute nodes that you want to add. For more information, see Work with vSwitches.

• Sufficient unused Elastic Compute Service (ECS) instance quotas are available in the region of the compute nodes that you want to add. For more information, see View and increase instance quotas.

Procedure

1. Open the Cluster page.

   1. Log on to the E-HPC console.

   2. In the top navigation bar, select a region.

   3. In the left-side navigation pane, click Cluster.

2. On the Cluster page, find the cluster that you want to scale out, and click Resize to the right of the cluster card.

3. In the Resize panel, complete the node configurations.

   When you scale out the cluster, you can add new nodes, existing nodes, or on-premises nodes. You can click a corresponding tab based on your requirements.

   Create Node

   Configure the parameters listed in the following table and click Buy Now.

   Parameter	Description
   Zone	The zone of the compute nodes that you want to add. The compute nodes that you want to add and the cluster can reside in different zones.
   vSwitch ID	The vSwitch of the compute nodes that you want to add.
   Pricing Model	The billing method of the compute nodes that you want to add. Valid values: Subscription: You can purchase or renew compute nodes by week, month, or year. Pay-As-You-Go: You are charged for compute nodes on an hourly basis. Preemptible Instance: Preemptible instances are a type of on-demand instances that are offered at a discounted price compared with pay-as-you-go instances. For more information, see Overview of instances.
   Quantity And Type of Instances to be Added	Select the number and instance type of the compute nodes that you want to add. You can add a maximum of 500 compute nodes. If you want to add more than 500 compute nodes, submit a ticket.
   Image Type and Image	The following image types are supported: public image, custom image, shared image, Alibaba Cloud Marketplace image, and community image. The image types that you can select depend on the specified region and zone and whether the current Alibaba Cloud account has available image resources. The image types that are displayed on the console take precedence. Select the image that you want to deploy on the compute nodes based on the image type. Take note of the following items: The image OS of the compute nodes that you want to add is the same as that of the compute nodes in the cluster. For example, if the operating system of the compute nodes in the cluster is CentOS, only a CentOS image can be selected. The major OS version of the compute nodes that you want to add is the same as that of the existing compute nodes in the cluster. For example, if the OS version of the existing compute nodes in the cluster is CentOS 7.x, the version of the compute nodes that you want to add must be CentOS 7.x. If you set Image Type to Custom Image, the custom image that you select must be created from compute nodes, not from logon nodes or management nodes. Otherwise, exceptions may occur when you scale out the cluster.
   Assign Public IP Address	If the node that you want to add needs to access the Internet, you can turn on the switch. Configure the billing method for the bandwidth, and maximum outbound bandwidth.
   Whether to use DNS	Specify whether to use Alibaba Cloud DNS to resolve the domain mains of the compute nodes. Only Alibaba Cloud DNS PrivateZone is supported.
   Queue	The queue to which the compute nodes are added.
   eRDMA	After you turn on eRDMA, the compute nodes are bound to remote direct memory access (RDMA) elastic network interfaces (ENIs) and can use high-performance RDMA network services. For more information, see Overview of eRDMA.
   Hostname Prefix and Hostname Suffix	Configure a prefix and suffix for the hostnames of the compute nodes based on your needs. This facilitates the management of multiple compute nodes.
   System Disk	Select the type and size of the system disk used by the compute nodes that you want to add, and configure whether to enable Hyper-Threading (HT). Note By default, HT is enabled for all ECS instances. For specific ECS instance types, you can disable HT for better performance. For more information, see Instance type limits and Disable HT for compute nodes.
   Data Disk	If you want to attach additional data disks to the compute nodes, click Add Data Disk and configure the type, size, and quantity for the new data disks.

Result

After you scale out the cluster, the added compute nodes automatically install and initialize the applications in the cluster. The original compute nodes are not affected.

To query the status of the added compute nodes, choose Resource Management > Nodes in the left-side navigation pane. Select the cluster that you scaled out from the Cluster drop-down list. Select Compute Node from the Node Type drop-down list. If the compute nodes are in the Running state, the cluster is scaled out.