vMSC Solutions with Inspur MCS InMetro

Products

• VMware vSphere ESXi

Issue/Introduction

This article provides information about deploying VMware vSphere Metro Storage Cluster across two data centers using Inspur MCS InMetro. With vSphere 6.0, virtual storage devices can be enabled in Metro Storage Cluster configurations.

Note: This solution is partner supported, for more information, see VMware Compatibility Guide - Partner Verified and Supported Products (PVSP).

Resolution

What is Inspur Multiple Controller System?

Inspur Multiple Controller System is capable of managing storage devices and stored data and helping application servers perform data operations. The software it provides includes host plug-in, MCS core software, system management, and control platform, which interact with each other to implement a variety of functions such as storage, backup and disaster recovery in an intelligent, efficient and cost effective manner.
For more details, contact Inspur customer service.

What is InMetro

The InMetro function offered by Inspur MCS allows for service continuity hardware failures, power outages, connection failures, and natural disasters such as fires and floods. Technologies such as synchronous remote copy, asynchronous remote copy with change volumes and uninterrupted data migration are applied.
InMetro keeps all nodes of an IO group at the same site, and each of the two IO groups has replica data so that even a single site can maintain complete read and write performance. InMetro allows multiple volumes to be combined within a consistency group so the data for each volume in the application can be consistently maintained. This greatly improves the application scenario using InMetro disaster recovery, since it is within a single cluster and does not involve cross-cluster remote data replication. InMetro uses asynchronous remote copy technology that adds change volumes to keep the data through resynchronization, allowing a site to continuously provide disaster recovery throughout the life cycle. InMetro allows the user to assign the host’s site so that it can access the nearest copy. The host will give preference to use the nearest copy, but another copy may be used at a failure. Host and storage are distributed at two different fault sections or faulty sites. As shown in Figure 1, nodes of an IO group are at the same site, and each volume is visible as a single object to two sites (I/O groups). The synchronization between the two IO groups is enabled through Metro Mirror, as seen in Figure 2. No matter which copy accepts the host IO, it will synchronize to the other copy. Synchronous copy cannot be started or stopped. It is automatically controlled by the storage microcode.

Figure 1

Figure 2

 

For more details, please contact Inspur customer service.

What is VMSC?

For more information, see VMware vSphere Metro Storage Cluster Recommended Practices.

InMetro Quorum

We have storage quorum disks or IP quorum applications for these scenarios. The site, which wins the quorum, keeps running for the hosts. And the other site stops for the reconnection.

Configuration requirements

• The quorum site must be set, it can be another Inspur Storage or a VM on the ESXi and can run java.
• The ESXi hosts in both data centers must have a private network on the same IP subnet and broadcast domain. Preferably management and vMotion traffic are on separate networks.
• The datastore must be active, and accessible both esxi host in both data centers.
• vCenter Server must be able to connect to ESXi hosts in both data centers.

VMware environment

• ESXi 5.x, 6.0, 6.5
• For the most up-to-date information on the recommended version of ESXi, refer to Inspur Multiple Controller System release notes or contact Inspur customer service.

Solution Overview

Two site hosts that create HA clusters through vSphere and two storage systems that create the InMetro cluster are needed. The vSphere Management, vMotion, and virtual machine networks are connected using a redundant network between the two sites. In the storage InMetro, using the virtual storage site as the quorum.

Test Scenarios

Scenario	Storage behavior	Impact on VMware HA
Single ESXi host failure	None	VMware HA successfully initiates all VMs based on HA relevance
Storage to host path failure	None	vSphere HA initiates the virtual machine on another host
Single site storage failure	Storage switch is done by the InMetro A/A function	VMs on VMware ESXi hosts will not be affected
A LUN failure on storage	Taken over by another LUN should an InMetro A/A LUN failure occur	None
Single site host failure	None	VM switched to the available site host by VMware HA
Single site host and storage failure	Switched to another site by InMetro	Switched to the available host by VMware HA
Single storage path failure	Another site path initiated by InMetro	No impact on ESXi host
Disconnect the FC link of the external quorum storage	No impact on the A/A volume	No impact on the ESXi host; warning in the storage A/A system disappears if FC is reconnected