Enable OS max connections and ports

ubuntu.sh

# Check number of CPUs
grep ^processor /proc/cpuinfo | wc -l

# set maximum number of open files (current session)
ulimit -u 10000
ulimit -n 10000

# Modify number open files
vi /etc/security/limits.conf
# *       soft    nofile   64000
# *       hard    nofile  64000
# root       soft    nofile   64000
# root       hard    nofile  64000

# Max file size
vi /etc/sysctl.conf
fs.file-max = 2097152

# Enable session limits
vi /etc/pam.d/common-session
# session required pam_limits.so
vi /etc/pam.d/common-session-noninteractive

# restart
sysctl -p

echo 6400 64000 > /proc/sys/net/ipv4/ip_local_port_range

sudo -u nginx bash -c "ulimit -a"