Building a SQL Cluster on Tencent Cloud (QCloud) – Step‑by‑Step Guide

Author Introduction: Li Sida, Microsoft MVP, certified instructor, and system operations engineer, shares his experience in building a SQL Cluster on a public cloud.

The difficulty of setting up a SQL Cluster on domestic public‑cloud providers is well known; the challenge lies in many detailed steps rather than the core complexity.

Why choose Tencent Cloud (QCloud)? QCloud retains the most native Windows support among Chinese public clouds, making it suitable for Windows‑based experiments.

The guide explains why a self‑built SQL Cluster can be preferable to the PaaS MSSQL offering: it provides a semi‑flexible, semi‑automated architecture that balances cost, management overhead, and risk for companies transitioning to the cloud.

Required Servers (example configuration):

1. Q-DC01 – DC role – 192.168.108.188 – Annual billing – S1,2C4G, no external network 2. Q‑SG01 – Shared storage – 192.168.108.206 – Annual billing – I1,4C16G, no external network 3. Q‑SQL01 – SQL Node1 – 192.168.108.254 – Pay‑as‑you‑go – I1 or S1, 8C32G, no external network 4. Q‑SQL02 – SQL Node2 – 192.168.108.114 – Pay‑as‑you‑go – I1 or S1, 8C32G, no external network

The architecture consists of a private VPC, a domain controller (DC), shared storage, and two SQL nodes.

Step 1 – Create a Private Network (VPC): Build a private network so that the machines can communicate internally, solving DNS and SRV requirements for Active Directory.

Step 2 – Create a Project Group: In the user center, create a new project to tag and manage the resources; this helps separate server types and track consumption.

Step 3 – Purchase the Servers: Follow the screenshots to select custom images for Q‑SG01, Q‑SQL01, and Q‑SQL02, and configure the specifications as listed above.

Step 4 – Set DC Policy: Increase the local administrator password complexity (include letters, numbers, special characters) to ensure login after reboot.

Step 5 – Rename and Reboot the DC: After renaming the machine, reboot it; note that most Chinese public clouds do not support renaming or password changes from the console.

Step 6 – Build the AD Domain: Use Server Manager to add the AD Domain Services role, follow the wizard screenshots, and accept default settings.

Step 7 – Promote the Server to a Domain Controller: Run the promotion wizard, input the domain name, set a recovery mode password, choose a backup folder, and complete the installation.

Step 8 – Join the Three Nodes to the Domain: Change each node’s DNS to point to the DC (192.168.108.188), verify connectivity (ping q‑vmcloud.com), rename the hosts if needed, and reboot to complete domain join.

Appendix – Observations:

1. High‑IO local SSD size scales with configuration, which may be inefficient for storage‑intensive databases. 2. Many Chinese public clouds skip the sysprep step, resulting in identical SIDs; consequently, VMs created from the same image cannot join the domain. QCloud provides a solution (see https://www.qcloud.com/document/product/213/4829) that works across platforms.

The recommended workflow is: create a VM → run sysprep → capture a custom image → use that image for subsequent VM creation.

This series of articles will continue to be published; stay tuned for more cloud‑native infrastructure tutorials.