Installing and Administering Internet Services

Chapter 4 157
Installing and Administering sendmail
Troubleshooting sendmail
Understanding syslog Entries
sendmail logs the following:
• Failures beyond its control (SYSERR).
• Administrative activities (for example, rebuilding the aliases
database, and killing and restarting the daemon).
• Events associated with mail transactions.
Log entries marked SYSERR indicate either system failures or
configuration errors and may require the attention of the system
administrator.
Each system log entry for a mail transaction has a queue ID associated
with it. All log entries for the same input message have the same queue
ID. Log level is normally set to 10 in the configuration file. At this level,
the following information is logged for each delivery:
message-id= If a message had a Message ID header line when it
was input to sendmail, this is logged. sendmail can
also be configured to add a Message ID header line if
none is present. This ID uniquely identifies a message
and can be used to trace the progress of a message
through mail relays.
from= The sender of the message and the message size are
logged.
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 non-local), 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 Several messages that are of interest only when debugging.
16 Verbose information regarding the queue.