3.1.12 Ensure syslog messages are not lost due to size

Information

PostgreSQL log messages can exceed 1024 bytes, which is a typical size limit for traditional Syslog implementations. When syslog_split_messages is off, PostgreSQL server log messages are delivered to the Syslog service as is, and it is up to the Syslog service to cope with the potentially bulky messages. When syslog_split_messages is on, messages are split by lines, and long lines are split so that they will fit into 1024 bytes.

If syslog is ultimately logging to a text file, then the effect will be the same either way, and it is best to leave the setting on, since most syslog implementations either cannot handle large messages or would need to be specially configured to handle them. But if syslog is ultimately writing into some other medium, it might be necessary or more useful to keep messages logically together.

Rationale:

Impact:

Depending on the Syslog server in use, log messages exceeding 1024 bytes may be lost or, potentially, cause the Syslog server processes to abort.

Solution

Execute the following SQL statement(s) to remediate this setting:

postgres=# alter system set syslog_split_messages = 'on';
ALTER SYSTEM
postgres=# select pg_reload_conf();
pg_reload_conf
----------------
t
(1 row)

Default Value:

on

See Also

https://workbench.cisecurity.org/benchmarks/11861

Item Details

Category: AUDIT AND ACCOUNTABILITY

References: 800-53|AU-4

Plugin: PostgreSQLDB

Control ID: 170f548a10c51d1eb682918010f38133ed48d2e28ed1787cf56c702ec067d277