This topic describes the access logs of Classic Load Balancer (CLB). If you use CLB Layer 7 listeners, you can use the access log data to debug errors, locate issues, and analyze user behaviors. CLB is interfaced with Simple Log Service, which can record and store access logs of CLB to help you efficiently analyze log data and locate errors.
What are access logs?
CLB access logs can be used to record detailed information about all requests that are sent to CLB. The information includes the time when requests are sent, client IP addresses, network latency, request URLs, and server responses. As an ingress for Internet access, CLB distributes a large number of access requests. You can use access logs to analyze the activities and geographical distribution of client users and troubleshoot errors.
After you enable the access log feature for a CLB instance, access log data is collected and stored in a Logstore of Simple Log Service for log analysis. You can disable the access log feature at any time.
The access log feature of CLB is free of charge. You are charged only for Simple Log Service. For more information about the pricing and billing of Simple Log Service, see Billing overview.
Only Layer 7 CLB listeners support access logs.
Make sure that the HTTP header value does not contain
||. Otherwise, the exported logs may be misplaced.
Benefits
The access log feature of CLB provides the following benefits:
Ease of use
Allows developers and O&M engineers to spend less time in log management and focus on business development and technical explorations.
Large storage capacity
CLB generates a large amount of access log data, which requires high log processing performance and costs. Simple Log Service supports higher performance at a lower cost than open-source log services.
Real-time processing
Scenarios such as DevOps, monitoring, and alerting require real-time log data. Traditional methods cannot meet this requirement. For example, it is time-consuming to perform extract, transform, and load (ETL) operations and data analytics by using tools such as Hive. A significant amount of effort is taken for data integration. The access log feature of CLB, in conjunction with the powerful big data computing capabilities of Simple Log Service, can analyze and process real-time log data within seconds.
Flexibility
Allows you to enable or disable the access log feature for a CLB instance. Simple Log Service is interfaced with CLB at the service level. You do not need to manually maintain Simple Log Service.
References
For more information about Simple Log Service, see What is Simple Log Service?.
For more information about how to manage CLB access logs, see Configure a CLB access log.
If you use CLB Layer 7 listeners and want to troubleshoot errors for backend servers, you can analyze the access log data to locate errors. CLB is interfaced with Simple Log Service, which can record and store access logs of CLB to help you efficiently analyze log data and locate errors. For more information, see Use access logs to locate unhealthy backend servers.