Survey Application Overview

An application migration survey should start with general information collection, followed by detail collection. It should be continuously iterated and lasts for the entire cloud migration period. In the early stage, the survey focuses on the application overview. In the migration phase, each application needs to be surveyed thoroughly to learn the detailed deployment architecture and component information. The application survey needs to be conducted by the application architects and application O&M administrators of all the service domains.

The survey of the application overview is conducted in the evaluation and planning phase. Generally, the applications are surveyed layer by layer in the following sequence: service domains, service systems, and application modules, as shown in the following figure.

Figure 1 Application overview example

The application overview survey methods, arranged from easiest to hardest, are as follows:

• Knowledge base: Some companies have well-developed knowledge bases and already have documents describing the application overview. In this case, you can directly obtain the information. Note that the document information in the knowledge bases may be outdated. Align and confirm with the service owners on it.
• CMDB: Some companies' CMDB systems have information about all applications. You can export application information from the CMDB, classify the information by service domain and service system, and align and confirm the information with the service owners.
• Observable platform: Some companies have built application observability platforms, such as Datadog and Huawei Cloud APM. On these platforms, you can check the invocation relationships between applications and develop the application overview.
• Survey and interview: Interview the service domain owners and record the system and application information of the domains. Develop an overview after completing all the service domain surveys.