执行shell命令在AWS中不起作用

Question

I'm facing problem to execute shell command in AWS but it works normally in my local computer. What I've used is pasted below:

$cmd='ffmpeg -i media/dream_theatre.jpg -r 1 media/66_dream_theatre.avi';
$output = shell_exec($cmd);

Same script works in my local computer but does not in AWS. However when I type this ffmpeg -i media/dream_theatre.jpg -r 1 media/66_dream_theatre.avi in AWS terminal CLI it works normally so it confirms correct installation of ffmpeg in AWS.

Answer 1

You probably don't have ffmpeg in the default PATH . Try replacing ffmpeg with the result of which ffmpeg .

Answer 2

I was trying a different shell command, but it didn't work in AWS Ubuntu instance although it worked locally. From a few other answers, I got to know that apache should operate as root.

Depending on your installation, you'll have to go to /etc/apache2/conf/httpd.conf or in LAMP/Ubuntu/Apache's case, it was

/etc/apache2/apache2.conf

Look for Users and Groups in the file and change it to root (not recommended for production servers). Apache might throw an error, that goes something like

Apache has not been designed to serve pages while running as root

In my case, I'm running ubuntu instance on AWS, so I just gave Users and Groups as 'ubuntu', and shell_exec started working on PHP :)