When purchasing a data disk for a Hong Kong CN2 cloud server, the biggest mistake is simply copying what others buy. A 50GB data disk might be more than enough for a personal blog, whereas a 200GB disk for an e-commerce site could run out of space in less than six months. What makes the difference? It’s not the technology, but the nature of the business.

　　You need to understand the distinct roles of the system disk and the data disk: the system disk holds the operating system and runtime environment, while the data disk stores website files, databases, logs, and user-uploaded content. The size of the data disk you choose depends on what you store on it and how quickly that data grows.

　　Why you shouldn't choose a data disk based on "gut feeling"

　　First, let's look at some typical configurations for Hong Kong CN2 cloud servers on the market to give you a sense of the standard scale:

　　2 vCPU/1GB RAM: 30GB data disk; 2 vCPU/2GB RAM: 40GB data disk; 4 vCPU/4GB RAM: 50GB data disk; 4 vCPU/8GB RAM: 60GB data disk; 8 vCPU/8GB RAM: 70GB data disk; 16 vCPU/32GB RAM: 80GB data disk; 32 vCPU/48GB RAM: 100GB data disk.

　　This configuration logic reveals one thing: the default data disk size scales with the CPU and RAM. Higher-end configurations come with larger default disks. However, "default" doesn't necessarily mean "right for you." You might use a 4 vCPU/4GB RAM server for a blog containing only a few dozen articles—in which case you wouldn't even use up 30GB—or you might use the same configuration for an image-heavy site, where 50GB could fill up in less than three months.

　　There is only one criterion for your decision: what kind of data your business writes to the disk, and how fast it accumulates.

　　Data disk capacity planning based on business type

　　Personal blogs and content sites: 20GB–40GB

　　For WordPress blogs, personal technical sites, and lightweight news/information sites, data disk usage primarily stems from articles, thumbnails, themes/plugins, and databases. For a text-heavy WordPress site, 200 articles plus thumbnails typically occupy between 1GB and 3GB of space. When including theme files, plugins, and the database, the entire site package usually stays under 5GB. Even for a blogger with a high update frequency, the accumulated data over a year would likely amount to just over a dozen gigabytes.

　　Guideline: If you only write articles occasionally and include a few accompanying images, a 20GB data disk is more than sufficient. If you plan to operate the site long-term and include a large number of screenshots and charts in your articles, a 30GB–40GB disk is a safer bet. Anything over 40GB would be wasteful for a content-focused blog.

　　Corporate Websites and Showcases for Foreign Trade Enterprises: 30GB–50GB

　　The data composition of a corporate website is similar to that of a blog, but it typically involves more product images, corporate qualification documents, promotional PDFs, and the like. For a medium-sized B2B foreign trade website—featuring dozens to hundreds of products (each with 3–5 images) alongside company profiles, case studies, and news updates—the total data volume usually falls between 5GB and 15GB.

　　However, if the site is used by a team—where domestic sales staff log in daily to update products and upload images—data growth will be continuous. Starting at 30GB and aiming for 50GB provides a comfortable range that meets the showcase needs of most small and medium-sized enterprises.

　　Cross-Border E-commerce Standalone Sites: Starting at 50GB–100GB

　　Cross-border e-commerce sites are heavy consumers of data disk space, and their data growth curve is much steeper than that of standard websites.

　　Typical data composition for a self-hosted WooCommerce or Shopify site includes: product images (at least 3–5 per SKU), order data, user account information, inventory snapshots, and marketing materials. If you have fewer than 50 SKUs, a 50GB data disk might suffice initially. However, product images are constantly updated for promotional campaigns, and the order database continues to expand.

　　Key Risk: Many e-commerce beginners store images directly on the server's data disk instead of using object storage. Once traffic surges during promotional seasons, images uploaded by users and customer service staff will rapidly consume storage space. A starting capacity of 50GB is recommended; additionally, plan for a "CDN + Object Storage" architecture, keeping only core business data and database files on the data disk.

　　Video/Live Streaming/Content Distribution: 100GB minimum; no upper limit

　　Video-related services have storage requirements on a completely different scale compared to other types of businesses. A single 1080p video file can easily range from hundreds of megabytes to several gigabytes. If the platform needs to store user-uploaded videos, live stream replays, and transcoded files in various resolutions, 50GB might not even be enough for the source file of a single popular video.

　　The best practice for such services is to store only indices and temporary files on the data disk, while keeping video source files in object storage or a dedicated storage cluster. However, if your business is small-scale and you prefer to store videos directly on the data disk, 100GB is the starting point. As content accumulates, you may need 200GB, 500GB, or even more.

　　Database Servers: Dedicated data disk; plan for at least double the estimated data volume

　　If your data disk is dedicated to running MySQL or PostgreSQL, the capacity planning logic differs significantly from that of a standard website.

　　Database disk consumption consists of three components: data files, index files, and transaction logs (binlog/redo log). Taking MySQL as an example, InnoDB's `ibdata` files and the `.ibd` files for each table are the primary consumers of space; binlogs will grow continuously if not purged, potentially increasing by anywhere from tens of megabytes to several gigabytes per day.

　　Professional Advice: The initial capacity of your database data disk should be at least twice your projected data volume for the next three years. This is not wasteful; it reserves space for index expansion, temporary tables, backups, and fragmentation. It is also recommended to keep 20% of the disk space free, as a full disk can degrade database performance.

　　Data Disk Expansion Process: What to do when you run out of space

　　Data disks support online expansion, so there is no need to reinstall the operating system. However, the process involves one extra step compared to expanding the system disk, as you must manually mount the disk and extend the partition. Step 1: Create a snapshot backup. Always create a snapshot before expanding capacity to prevent data loss due to operational errors.

　　Step 2: Expand the data disk via the console. Log in to the cloud server console, locate the data disk, and select the expansion option. Note that data disks support expansion but not reduction, so leave some headroom when selecting the new capacity.

　　Step 3: Log in to the server to extend the partition and file system.

　　Expanding capacity on Windows systems is simpler: after expanding the disk in the cloud console, open "Disk Management" on the server, right-click the partition associated with the data disk, select "Extend Volume," and follow the wizard's instructions.

　　The size of the data disk you purchase should not be determined by your CPU or memory, but by the data your application will store. 20 GB is sufficient for a blog, while an e-commerce site should start with 50 GB; for database disks, calculate the required capacity by doubling your expected data volume. Do not skimp on capacity; the losses incurred when a website becomes inaccessible because the data disk is full far outweigh the cost of purchasing a few extra gigabytes.