1. Find out what the current open file descriptor limit is.
$more /proc/sys/fs/file-max
753825
or
$sysctl -a | grep fs.file-max
fs.file-max = 753825
2. View how many open file descriptors are currently being used.
$more /proc/sys/fs/file-nr
4080 0 753825
3. Edit the kernel paramneter file /etc/sysctl.conf and add line “fs.file-max=[new value]” to it.
vi /etc/sysctl.conf
fs.file-max = 1000000
4. Apply the changes.
sysctl -p
fs.file-max = 331287
User Level FD Limits
The above procedure sets system-wide file descriptors (FD) limits. However, you can limit httpd (or any other users) user to specific limits by editing /etc/security/limits.conf file, enter:# vi /etc/security/limits.conf
Set httpd user soft and hard limits as follows:httpd soft nofile 4096
httpd hard nofile 10240
Save and close the file. To see limits, enter:# su - httpd
$ ulimit -Hn
$ ulimit -Sn
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