这是logwatch 邮件日志:
--------------------- clam-update Begin ------------------------ 
 No updates detected in the log for the freshclam daemon (the
 ClamAV update process).  If the freshclam daemon is not running,
 you may need to restart it.  Other options:
 A. If you no longer wish to run freshclam, deleting the log file
    (default is freshclam.log) will suppress this error message.
 B. If you use a different log file, update the appropriate
    configuration file.  For example:
       echo "LogFile = log_file" >> /etc/logwatch/conf/logfiles/clam-update.conf
    where log_file is the filename of the freshclam log file.
 C. If you are logging using syslog, you need to indicate that your
    log file uses the syslog format.  For example:
       echo "*OnlyService = freshclam" >> /etc/logwatch/conf/logfiles/clam-update.conf
       echo "*RemoveHeaders" >> /etc/logwatch/conf/logfiles/clam-update.conf
 ---------------------- clam-update End -------------------------