PHP Warning: exec() has been disabled for security reasons in
PHP Warning: exec() has been disabled for security reasons in /home/cacti/lib/poller.php on line 126
PHP Warning: popen() has been disabled for security reasons in /home/cacti/lib/rrd.php on line 52
原因：在php.ini中存在 disable_functions配置，默认配置中，cli执行函数都是被 禁止的，如果需要的话，需要在php.ini中将 disable_functions = exec , popen, system …. ，将你需要执行的函数从列表中删掉在重启web服务即可 。