Logging Overview

You can enable logging to facilitate analysis or audit as required. Access logs enable a bucket owner to analyze the property, type, or trend of requests to the bucket in depth. When the logging function of a bucket is enabled, OBS will log access requests for the bucket automatically, and write the generated log files to the specified bucket (target bucket).

OBS can record bucket access requests in logs for request analysis and log audit.

Logs occupy some OBS storage space rented by users, causing extra fees. For this reason, OBS does not collect bucket access logs by default.

The log files are generated and uploaded by OBS to the bucket where the logs are stored. Therefore, OBS requires the authorization to upload the generated log files. Therefore, before configuring logging for a bucket, you need to create an IAM agency for OBS and add this agency when configuring logging for the bucket. By default, when configuring permissions for an agency, you only need to grant the agency the permission to upload log files (PutObject) to the bucket for storing log files. In the following example, mybucketlogs is the bucket. If the default encryption function is enabled for the log storing bucket, the IAM agency also requires the KMS Administrator permissions in the region where the log storing bucket resides.

{
    "Version": "1.1",
    "Statement": [
        {
            "Action": [
                "obs:object:PutObject"
            ],
            "Resource": [
                "OBS:*:*:object:mybucketlogs/*"
            ],
            "Effect": "Allow"
        }
    ]
}

After logging is configured, you can view operation logs in the bucket that stores the logs in approximately fifteen minutes.

The following shows an example access log of the target bucket:

787f2f92b20943998a4fe2ab75eb09b8 bucket [13/Aug/2015:01:43:42 +0000] xx.xx.xx.xx 
787f2f92b20943998a4fe2ab75eb09b8 281599BACAD9376ECE141B842B94535B  REST.GET.BUCKET.LOCATION 
- "GET /bucket?location HTTP/1.1" 200 - 211 - 6 6 "-"  "HttpClient" - -

The access log of each bucket contains the following information.