ubuntu server init

init.sh

#!/bin/bash  

cat >> /etc/security/limits.conf <<EOF
root        soft   nofile       65535 
root        hard   nofile       65535 
*           soft   nofile       65535 
*           hard   nofile       65535 
EOF


cat >> /etc/sysctl.conf <<EOF
net.ipv4.tcp_fin_timeout = 1  
net.ipv4.tcp_mem = 94500000 915000000 927000000 
net.ipv4.tcp_timestamps = 0 
net.ipv4.tcp_synack_retries = 1 
net.ipv4.tcp_syn_retries = 1 
net.core.rmem_max = 16777216 
net.core.wmem_max = 16777216 
net.core.netdev_max_backlog = 262144 
net.core.somaxconn = 20480 
net.ipv4.tcp_max_orphans = 3276800 
net.ipv4.tcp_max_syn_backlog = 262144 
net.core.wmem_default = 8388608 
net.core.rmem_default = 8388608
net.ipv4.tcp_congestion_control = bbr
net.core.default_qdisc = fq
vm.swappiness = 70
net.ipv4.icmp_echo_ignore_all = 1
EOF

/sbin/sysctl -p

# make rc.local start up
printf '%s\n' '#!/bin/bash' 'swapon /swapfile' 'exit 0' |tee -a /etc/rc.local
chmod +x /etc/rc.local

# add swapfile 1G
dd if=/dev/zero of=/swapfile bs=128 count=1024k
mkswap /swapfile
chown root:root /swapfile
chmod 0600 /swapfile

# enable zswap
#cat /etc/default/grub  |grep -v "GRUB_CMDLINE_LINUX_DEFAULT"  > /tmp/grub.cmdline
#default_grub_cmd=`cat /etc/default/grub  |grep "GRUB_CMDLINE_LINUX_DEFAULT"| awk  -F"\"" '{print $2}'`
#zswap="zswap.enabled=1 zswap.max_pool_percent=10"
#echo "GRUB_CMDLINE_LINUX_DEFAULT=\"$default_grub_cmd $zswap\"" > /etc/default/grub
#cat /tmp/grub.cmdline >> /etc/default/grub
#update-grub
sed -i "s/MODULES=most/MODULES=dep/g" /etc/initramfs-tools/initramfs.conf
sed -i "s/FRAMEBUFFER=y/FRAMEBUFFER=n/g" /usr/share/initramfs-tools/conf-hooks.d/cryptsetup

#upgrade
apt remove --purge snapd
apt update && apt upgrade -y


cat << EOF 
+-------------------------------------------------+ 
|               optimizer is done                 | 
|   it's recommond to restart this server !       | 
+-------------------------------------------------+ 
EOF