Too many open files : Nginx (log)

gistfile1.txt

ERROR:
++++++

2021/07/03 08:20:10 [alert] 8744#8744: setrlimit(RLIMIT_NOFILE, 2165535) failed (1: Operation not permitted)
2021/07/03 08:20:10 [alert] 8743#8743: setrlimit(RLIMIT_NOFILE, 2165535) failed (1: Operation not permitted)
2021/07/03 08:20:22 [alert] 8814#8814: setrlimit(RLIMIT_NOFILE, 2165535) failed (1: Operation not permitted)
2021/07/03 08:20:22 [alert] 8815#8815: setrlimit(RLIMIT_NOFILE, 2165535) failed (1: Operation not permitted)
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Workaround:
+++++++++++

#please note that I am using runcloud.io installation thats why nginx is nginx-rc, for your case it may very well be nginx only. 

systemctl edit nginx-rc
#that will create the file /etc/systemd/system/nginx-rc.service.d/override.conf
#then add
[Service]
LimitNOFILE=1048576
LimitNPROC=1048576
#save and close

systemctl daemon-reload

systemctl restart nginx-rc

cd /

find / -name nginx.conf 

#this command will give you the nginx.conf file path

nano /etc/nginx-rc/nginx.conf

#here, check the user line, in our case it was: user runcloud-www runcloud-www;

chown runcloud-www:runcloud-www nginx.conf

chown runcloud-www:runcloud-www nginx.conf.default

nano nginx.conf
#comment out worker_rlimit_nofile 2165535;
#save and close

sysctl -p /etc/sysctl.conf
nginx-rc -t
nginx-rc -S reload
systemctl restart nginx-rc.service

#after restart of nginx-rc.service, check tail -100f /var/log/nginx-rc/error.log