[Official Guidelines] How to Migrate Business to Tencent Cloud? Offline/Online Data Migration Solutions and Common Error Reporting Solutions
With the deepening of enterprise digital transformation, it has become the norm to migrate business from local IDC or other cloud vendors to Tencent Cloud. The core pain points of migration are:
How can I guarantee zero data loss and minimize downtime?
The first part: "physical examination" before migration-architecture evaluation and scheme selection
Before moving any line of code, detailed research must be done.
1. Business research and dependency analysis
Component list: sorting application servers (ECS/CVM), databases (MySQL/Redis), object storage (OSS/COS), and load balancing (SLB/CLB).
Network topology: Confirm the network environment (public network, leased line, or VPN) of the origin.
Bandwidth assessment: measures the upstream bandwidth of the source station, which determines the time required for migration.
2. Selection of migration scheme
There are two paths based on the business's tolerance for downtime:
Online migration (hot migration): applicable to core business. Through the incremental synchronization technology, data is transferred without stopping the service of the source station, and only a second-level flash occurs when the DNS is switched.
Offline migration (cold migration): applicable to non-core business or ultra-large-scale data (PB level). Data is packaged first and transmitted through physical media or leased lines. Business writing must be suspended during migration.
Part 2: Core Migration Scenarios and Tool Chains
Tencent Cloud provides a complete set of migration tools, collectively known
MSP(Migration Service Platform)
。
1. Host migration: console one-click operation (Go2Cloud)
Tencent Cloud Host Migration Service (SMS) supports the migration of physical machines, virtual machines (VMware/OpenStack) or other cloud platform cloud servers to Tencent Cloud CVM.
Online migration process: Install the migration client on the source server. Create a migration task in the Tencent Cloud console and select Online Migration ". The system automatically creates a temporary transit instance on the Tengxun cloud side to transfer data through Rsync or block-level replication. After full replication is completed, the incremental synchronization phase is entered.
2. Database Migration: The Wonderful Use of DTS
Data Transfer Service (DTS) is the core of smooth database migration.
Key points of operation: structure migration: automatically synchronize table structure, view and stored procedure. Full migration: Transfer existing data to Tencent Cloud CDB. Incremental synchronization: This is the most critical step. DTS reads the binlog of the source database in real time and synchronizes it to the target database to ensure that the data on both sides is consistent in real time. Service cutover: when the delay drops to the millisecond level, modify the application connection string to point to the Tencent cloud database.
3. Massive Object Storage Migration: COS Migration
If you have several TB of pictures or videos in other cloud vendors, it is recommended to use
COS Migration Tools
。 It supports multi-threaded concurrent upload and can respond to network fluctuations through the breakpoint resume function.
Part Three:
Offline data migration solution (for very large data)
When the amount of data is too large to bear the Internet bandwidth (for example, more than 50TB),
Offline migration
is the only option.
Tengxun Cloud Migration Station (Cloud Starter): Tengxun Cloud will send a dedicated hardware storage device to your computer room.
Local Copy: Copy data to the device through the 10 Gigabit network port.
Logistics return: the equipment is sent back to tengxunyun computer room, and the engineer imports COS or cloud hard disk at high speed through the intranet.
Validation: Use MD5 validation to ensure data integrity.
The fourth part: common error analysis and solutions
During the migration process, you may encounter the following typical problems:
1. The migration progress bar is stuck at 0% or an error is reported
Connection Timeout
Reason: The source station security group or firewall did not allow Tencent cloud to transfer IP, or port 80/443/22 was restricted.
Resolution: Check the origin iptables; ensure that the migration client process (go2cloud_client) is running properly.
2. Database migration tips
Binlog format error
Cause: DTS online migration requires that the source database binlog must be in ROW format.
Solution: Modify the source database my.cn f configuration: binlog_format = ROW, and restart the service (note: restart will cause a short interruption).
3. Linux system cannot be started after migration (Kernel Panic)
Cause: Driver incompatibility (e. g. Virtio driver missing).
Solution: Run a script to check and install the virtio driver on the source server before migration. Tengxun cloud SMS tools are usually injected automatically, but for very old versions of the kernel (such as CentOS 5), manual processing is required.
4. Permission overflow or packet loss
Cause: The owner permission of the migrated file changes, or the internal network MTU value is inconsistent, resulting in large packet loss.
Solution: Use rsync -avz to maintain the permission attribute. Check the MTU settings of the VPC intranet. We recommend that you unify the settings to 1500.
Part 5: The "three-stage" strategy of smooth cutover
To ensure a foolproof migration, follow the following rhythm:
Pre-migration test: Pull up a set of shadow systems on the Tengxun cloud side, and use copies of production data for stress testing and functional verification.
Grayscale switching: through DNS weighted polling, first guide 10% of the traffic to tengxun cloud and observe 24-hour monitoring.
Full back-to-source preparation: At the beginning of the switch, the incremental data reverse synchronization (reverse DTS) of the source station is maintained. In case of unpredictable failures on the Tengxun cloud side, the source station can be switched back at any time to ensure high service availability.
Conclusion
Business migration is not a simple "copy and paste", but a sophisticated operation. Make good use of it
Tencent Cloud SMS,
DTS and MSP Platforms
, combined with detailed plans, in order to ensure that the business in the cloud to set sail steadily.
Tip: Before starting the migration, be sure to complete a full manual backup at the origin, which is the last line of defense for all technical operations.
