Log Locations

Common Log Locations:

Apache

Domain access logs:
  /usr/local/apache/domlogs/<DOMAIN>

Site and service error logs:
  /usr/local/apache/logs/error_log

SuExec audit log:
  /usr/local/apache/logs/suexec_log

SuPHP audit log:
  /usr/local/apache/logs/suphp_log

cPanel

Service status:
  /var/log/chkservd.log

Service status:
  /var/log/chkservd.log

Access and user actions:
  /usr/local/cpanel/logs/access_log

Exim

(see exim )

Fatal errors:
  /var/log/exim_paniclog

Incoming mail queue:
  /var/spool/exim/input

Exim Messages rejected based on ACLs or other policies:
  /var/log/exim_rejectlog

Exim Delivery and receipt:
  /var/log/exim_mainlog

IMAP, POP login attempts, transactions, fatal errors and spam scoring:
  /var/log/maillog
  /var/log/messages

System

Cron:
  /var/log/cron

Most other logs:
  /var/log/messages

MySQL database logs:
/var/log/mysqld.log

Full List of cPanel Logs

S.No     log file location     Description
1     Cpanel installation logs     /var/log/cpanel-install.log
2     Cpanel Access Logs     /usr/local/cpanel/logs/access_log
3     Cpanel Error Logs     /usr/local/cpanel/logs/error_log
4     Cpanel License Logs     /usr/local/cpanel/logs/license_log
5     Cpanel Login Logs     /usr/local/cpanel/logs/login_log
6     cPHulk Brute Force Logs     /usr/local/cpanel/logs/cphulkd.log
7     Cpanel/WHM Accounting (account creations, deletions, etc) Logs     /var/cpanel/accounting.log
8     Cpanel Bandwidth Logs     /var/cpanel/bandwidth/(account user name)
9     Cpanel/WHM Service monitor Logs     /var/log/chkservd.log
10     Cpanel Stats Daemon Logs     /usr/local/cpanel/logs/stats_log
11     Cpanel backup Logs     /usr/local/cpanel/logs/cpbackup
12     Update (UPCP) Log     /var/cpanel/updatelogs/update-(TIMESTAMP).log
13     cPanel/WHM webalizer/awstats logs     /usr/local/cpanel/logs/stats_log
14     SquirrelMail     /var/cpanel/squirrelmail
15     RoundCube     /var/cpanel/roundcube/log
16     Horde     /var/cpanel/horde/log
17     tailwatchd log     /usr/local/cpanel/logs/tailwatch_log
18     EasyApache Build Logs     /usr/local/cpanel/logs/easy/apache/
19     Apache Access Logs     /usr/local/apache/logs/access_log
20     Apache Error Logs     /usr/local/apache/logs/error_log
21     Domain Access Logs     /usr/local/apache/domlogs/domain.com
22     Ftp Logs     /var/log/messages /var/log/xferlog (symlinked to /usr/local/apache/domlogs/ftpxferlog)
23     Exim Sent/received     /var/log/exim_mainlog
24     Rejected mail logs     /var/log/exim_rejectlog
25     Unexpected/Fatal Error Log     /var/log/exim_paniclog
26     Courier, Dovecot, SpamAssassin & IMAP     /var/log/maillog
27     Incoming mail queue     /var/spool/exim/input/
28     Mailman Logs     /usr/local/cpanel/3rdparty/mailmain/logs
29     mysql logs     /val/log/mysqld.log /var/lib/mysql/$(HOSTNAME).err
30     Tomcat Logs     /usr/local/jakarta/tomcat/logs/catalina.err /usr/local/jakarta/tomcat/logs/catalina.out
31     Cron Logs     /var/log/cron
32     ModSecurity Logs     /usr/local/apache/logs/modsec_audit.log /usr/local/apache/logs/modsec_debug_log
33     Named/Bind (DNS) logs     /var/log/messages
34     PostgreSQL database server logs     /var/log/pgsql
35     cPanel/WHM version checking     /usr/local/cpanel/version
36     SSH Logs     /var/log/secure

References

cPanel Log Locations Poster:

cPanel Log Locations Poster