Sometimes we need to test rewrite rule and log to see what happen, just put this on .htaccess file
RewriteLog /tmp/rewritelog
RewriteLogLevel 9
RewriteLog directive set the path to the log file. you can also set this directive to send log to a program. For a bit more complete information about this see here
valid values for RewriteLogLevel is 0-9
0 = no logging at all
9 = logging all possible information
see here for more complete explanation
don’t forget to turn on the RewriteEngine by putting this line
RewriteEngine on
