HP-UX Mailing Services Administrator's Guide

Configuring and Administering Sendmail
Troubleshooting Sendmail
Chapter 298
considered useful. Log levels above 11 are normally used only for
debugging purposes. We recommend that you configure syslogd to log
mail messages with a priority level of debug and higher. Sendmail’s
behavior at each log level is described in Table 2-5.
Table 2-5 Sendmail Logging Levels
Logging
Level
Behavior
0 No logging.
1 Major problems only.
2 Message collections and failed deliveries.
3 Successful deliveries.
4 Messages being queued (due to a host being down, and
so on).
5 Messages being added to the queue in routine
circumstances.
6 Unusual but benign incidents, such as trying to process
a locked queue file.
9 Log internal queue ID to external message ID
mappings. This can be useful for tracing a message as it
travels between several hosts.
10 The name of the mailer used, the host (if nonlocal), and
the user name passed to the mailer are logged. If the log
level is 10 or higher, Sendmail also reports this
information in -bv (verify) mode.
11 For successful deliveries to IPC mailers, the MX (mail
exchanger) host delivered to (if any) and the Internet
address used for the connection are logged.
12 All incoming and outgoing SMTP commands and their
arguments are logged at LOG_INFO.
13 Log bad user shells, world-writable files, and other
questionable situations.