Each domain's logs are stored at /usr/local/apache/domlogs/domain_name
The raw Apache logs (not the same as domain logs) live at /usr/local/apache/logs ... you will find several logs there:
access_log - Raw accesses
error_log - Errors for all accounts are stored here; each account's cPanel pulls entries for its own domain out of this log, and displays them in that account's cPanel Error Log.
modsec_debug_log - where mod_security writes its activity, if you have mod_security installed. This log is great for sorting out why Client XYZ is getting a 406 error on a particular page -- just look for the entry and it will show you which rule the page/call tripped up on.
suexec_log - All suexec activity is logged here, including errors & the reason for errors. Helpful for diagnosing clients' 500 errors.
Hope this helps!!!
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