It is important for a production server to set the maximum open file limit as you might get over limit on your web services, database services, email services, and etc.
First of all, you may list the maximum of open file limit as command below.
Then you may increase the file description limit as command below.
sysctl -w fs.file-max=150000
The above command force the kernel to limit the maximum open file limit but you will need to perform the change from /etc/sysctl.conf in case the setting change after a reboot.
Append the setting as below.
fs.file-max = 150000
Then save it and run the command as below.