RDS for PostgreSQL database log files

You can monitor the following types of log files:

RDS for PostgreSQL logs database activities to the default PostgreSQL log file. For an on-premises PostgreSQL DB instance, these messages are stored locally in log/postgresql.log. For an RDS for PostgreSQL DB instance, the log file is available on the Amazon RDS instance. These logs are also accessible via the AWS Management Console, where you can view or download them. The default logging level captures login failures, fatal server errors, deadlocks, and query failures.

For more information about how you can view, download, and watch file-based database logs, see Monitoring Amazon RDS log files. To learn more about PostgreSQL logs, see Working with Amazon RDS and Aurora PostgreSQL logs: Part 1 and Working with Amazon RDS and Aurora PostgreSQL logs: Part 2.

In addition to the standard PostgreSQL logs discussed in this topic, RDS for PostgreSQL also supports the PostgreSQL Audit extension (pgAudit). Most regulated industries and government agencies need to maintain an audit log or audit trail of changes made to data to comply with legal requirements. For information about installing and using pgAudit, see Using pgAudit to log database activity.

Publishing PostgreSQL logs to Amazon CloudWatch Logs

To store your PostgreSQL log records in highly durable storage, you can use Amazon CloudWatch Logs. With CloudWatch Logs, you can also perform real-time analysis of log data and use CloudWatch to view metrics and create alarms. For example, if you set log_statement to ddl, you can set up an alarm to alert you whenever a DDL statement is executed. You can choose to have your PostgreSQL logs uploaded to CloudWatch Logs during the process of creating your RDS for PostgreSQL DB instance. If you chose not to upload logs at that time, you can later modify your instance to start uploading logs from that point forward. In other words, existing logs aren't uploaded. Only new logs are uploaded as they're created on your modified RDS for PostgreSQL DB instance.

All currently available RDS for PostgreSQL versions support publishing log files to CloudWatch Logs. For more information, see Amazon RDS for PostgreSQL updates in the Amazon RDS for PostgreSQL Release Notes..

To work with CloudWatch Logs, configure your RDS for PostgreSQL DB instance to publish log data to a log group.

You can publish the following log types to CloudWatch Logs for RDS for PostgreSQL:

After you complete the configuration, Amazon RDS publishes the log events to log streams within a CloudWatch log group. For example, the PostgreSQL log data is stored within the log group /aws/rds/instance/my_instance/postgresql. To view your logs, open the CloudWatch console at https://console.aws.amazon.com/cloudwatch/.

aws rds modify-db-instance \
    --db-instance-identifier mydbinstance \
    --cloudwatch-logs-export-configuration '{"EnableLogTypes":["postgresql", "upgrade"]}'
   

aws rds modify-db-instance ^
    --db-instance-identifier mydbinstance ^
    --cloudwatch-logs-export-configuration '{"EnableLogTypes":["postgresql","upgrade"]}'
				

aws rds create-db-instance \
    --db-instance-identifier mydbinstance \
    --enable-cloudwatch-logs-exports '["postgresql","upgrade"]' \
    --db-instance-class db.m4.large \
    --engine postgres 
    			

aws rds create-db-instance ^
    --db-instance-identifier mydbinstance ^
    --enable-cloudwatch-logs-exports '["postgresql","upgrade"]' ^
    --db-instance-class db.m4.large ^
    --engine postgres