A set of environment of the company is accessed through VPN, which uses OpenVPN. At some time in the afternoon, some students reported that VPN login failed. Try it yourself, too. Log in to the server to view the VPN log information as follows

ERROR: Linux route delete command failed: external program exited with error status: 2

Solution: Remove the limit in the service startup file, and comment out the line LimitNPROC

vim /usr/lib/systemd/system/[email protected]

#LimitNPROC

Restart service

systemctl daemon-reload
systemctl restart [email protected]