sendmail log levels
The level of logging can be set for sendmail.
The default using a standard configuration table is level 9.
In order to activate logs, change the following file / line :
File to edit - /etc/sendmail.cf
Line to edit:
Log file will be created at:
Log name – maillog
Log location - /var/log
The levels are as follows:
0 No logging.
1 Serious system failures and potential security problems.
2 Lost communications (network problems) and protocol failures.
3 Other serious failures.
4 Minor failures.
5 Message collection statistics.
6 Creation of error messages, VRFY and EXPN commands.
7 Delivery failures (host or user unknown, etc.).
8 Successful deliveries and alias database rebuilds.
9 Messages being deferred (due to a host being down, etc.).
10 Database expansion (alias, forward, and userdb lookups).
20 Logs attempts to run locked queue files. These are not errors, but can be useful to note if your queue appears to be clogged.
30 Lost locks (only if using lockf instead of flock).
Additionally, values above 64 are reserved for extremely verbose debugging output. No normal site would ever set these.