Do you want to use nginx automatical crontab command to clear your /tmp/nginx_client/ folder,
but that command is not working causing the nginx to full your tmp folder,
First check via SSH that you have added the command line at crontab -e
You need to have added this:
0 */1 * * * /usr/sbin/tmpwatch -am 1 /tmp/nginx_client
You can always change the frequency of the cron, but the above is suggested by nginx
So if its listed there, then you are missing tmpwatch
Lets check if this is true:
Type in SSH: /usr/sbin/tmpwatch -am 1 /tmp/nginx_client
If it states that the directory does not exist or not found then you need to add tmpwath
So you need to install it, in order ngnix to work smoothly
So in SSH again type: yum install tmpwatch
And then to check if its working just type: /usr/sbin/tmpwatch -am 1 /tmp/nginx_client
Nginx will be working ok and no need to manually empty the /tmp/nginx_client folder again.