Why can't I find a specific request record in OSS access logs?
OSS access logs are delivered on a best-effort basis — not every request is guaranteed to appear in the logs. If a specific request record is missing, one of the following causes is most likely responsible.
CDN cache hit
When you use Alibaba Cloud CDN to accelerate access to OSS resources, a CDN cache hit means the request is served directly by CDN without reaching OSS. Because the request never arrives at OSS, OSS has no record of it.
To check whether CDN served the request from cache, download the offline logs provided by Alibaba Cloud CDN. For details, see Download logs.
Client-side interruption
If the request fails before reaching OSS — due to a network issue or a client configuration error — OSS cannot record it.
To diagnose the failure, check the exception output or log file from your SDK. For details, see Error handling.
Log delivery not guaranteed
OSS does not guarantee log delivery. In some cases, logs may not be successfully pushed.
Incorrect region endpoint
If you query a bucket using an endpoint from a different region, no log entry is generated for the intended bucket.
For example, calling GetBucketInfo for a bucket in China (Beijing) while using an endpoint for China (Shanghai) produces no log record in the China (Beijing) bucket's access logs. Make sure the endpoint matches the region where the bucket resides.