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Minimal install system init script
Note: This script is applicable to centos 7/8, Ubuntu1804, and it needs to be tested and adjusted according to the actual situation.
Functions included in this script:
- Allow the root user to log in using ssh
- close selinux
- turn off firewall
- set ps1
- Set the default editor to vim
- custom vim
- custom history command
- Modify kernel parameters
- Set resource limits
- Modify the software source
- Install common packages
- Set up time synchronization
- Modify the network card to the traditional command format
- Set IP address, etc.
[root@centos8 ~]# cat init_v1.sh
#!/bin/bash
#
#**************************************************
#Author: Xan_Yum
#QQ: 7993167
#Email: [email protected]
#Version: 1.0
#Date: 2021-11-03
#FileName: init_v1.sh
#Description: system init
#URL: https://waluna.top
#Copyroght (C): 2021 ALL rights reserved
#**************************************************
OS=`awk -F'"' '/PRETTY_NAME/{print $2}' /etc/os-release|tr ' ' '-'`
#1
set_ssh () {
if [[ $OS == Ubuntu-18.04* ]];then
sed -i.bak '/#PermitRootLogin/a PermitRootLogin yes' /etc/ssh/sshd_config
systemctl restart sshd
fi
echo -e "\e[32;1mPermit root login set complete\e[0m"
}
#2
disable_selinux () {
if [[ $OS == CentOS* ]];then
sed -i.bak 's/SELINUX=enforcing/SELINUX=disabled/' /etc/selinux/config
fi
echo -e "\e[32;1mSElinux already disabled,Restart to take effect\e[0m"
}
#3
disbale_firewall () {
systemctl disable --now firewalld &> /dev/null
echo -e "\e[32;1mFirewall already disabled\e[0m"
}
#4
set_ps1 () {
if [[ $OS == CentOS* ]];then
echo "PS1='\[\e[1;36m\][\u@\h \W]\\$ \[\e[0m\]'" >> /etc/profile.d/env.sh
. /etc/profile.d/env.sh
elif [[ $OS == Ubuntu* ]];then
echo 'PS1="\[\e[1;32m\][${debian_chroot:+($debian_chroot)}\u@\h \w]\\$ \[\e[0m\]"' >> .bashrc
. .bashrc
fi
echo -e "\e[32;1mPS1 already modify,Please login again\e[0m"
}
#5
set_default_text_editor_vim () {
echo "export EDITOR=vim" >> /etc/profile.d/env.sh
. /etc/profile.d/env.sh
echo -e "\e[32;1mdefault_text_editor already modify vim,Please login again\e[0m"
}
#6
set_vim () {
cat > ~/.vimrc <<EOF
set ts=4
set expandtab
set ignorecase
set cursorline
set autoindent
autocmd BufNewFile *.sh exec ":call SetTitle()"
func SetTitle()
if expand("%:e")=='sh'
call setline(1,"#!/bin/bash")
call setline(2,"#")
call setline(3,"#**************************************************")
call setline(4,"#Author: Xan_Yum")
call setline(5,"#QQ: 7993167")
call setline(6,"#Email: [email protected]")
call setline(7,"#Version: 1.0")
call setline(8,"#Date: ".strftime("%Y-%m-%d"))
call setline(9,"#FileName: ".expand("%"))
call setline(10,"#Description: The test script")
call setline(11,"#URL: https://waluna.top")
call setline(12,"#Copyroght (C): ".strftime("%Y")." ALL rights reserved")
call setline(13,"#**************************************************")
endif
endfunc
autocmd BufNewFile * normal G
EOF
echo -e "\e[32;1mVim already modify\e[0m"
}
#7
set_history () {
echo 'export HISTTIMEFORMAT="%F %T `whoami` "' >> /etc/profile.d/env.sh
echo -e "\e[32;1mHistory modify\e[0m"
}
#8
modify_kernel_parameters () {
mv /etc/sysctl.conf{
,.bak}
cat > /etc/sysctl.conf <<EOF
# Controls source route verification
net.ipv4.conf.default.rp_filter = 1
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1
# Do not accept source routing
net.ipv4.conf.default.accept_source_route = 0
# Controls the System Request debugging functionality of the kernel
kernel.sysrq = 0
# Controls whether core dumps will append the PID to the core filename.
# Useful for debugging multi-threaded applications.
kernel.core_uses_pid = 1
# Controls the use of TCP syncookies
# 表示是否打开TCP同步标签(syncookie),内核必须打开了CONFIG_SYN_COOKIES项进行编译,同步标签可以防止一个套接字在有过多试图连接到达时引起过载。
net.ipv4.tcp_syncookies = 1
# Disable netfilter on bridges.
# net.bridge.bridge-nf-call-arptables:是否在arptables的FORWARD中过滤网桥的ARP包
# net.bridge.bridge-nf-call-ip6tables:是否在ip6tables链中过滤IPv6包
# net.bridge.bridge-nf-call-iptables:是否在iptables链中过滤IPv4包
# net.bridge.bridge-nf-filter-vlan-tagged:是否在iptables/arptables中过滤打了vlan标签的包
net.bridge.bridge-nf-call-ip6tables = 0
net.bridge.bridge-nf-call-iptables = 0
net.bridge.bridge-nf-call-arptables = 0
# Controls the default maxmimum size of a mesage queue
kernel.msgmnb = 65536
# # Controls the maximum size of a message, in bytes
kernel.msgmax = 65536
# Controls the maximum shared segment size, in bytes
kernel.shmmax = 68719476736
# # Controls the maximum number of shared memory segments, in pages
kernel.shmall = 4294967296
# TCP kernel paramater
net.ipv4.tcp_mem = 786432 1048576 1572864
net.ipv4.tcp_rmem = 4096 87380 4194304
net.ipv4.tcp_wmem = 4096 16384 4194304
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_sack = 1
# socket buffer
net.core.wmem_default = 8388608
net.core.rmem_default = 8388608
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.core.netdev_max_backlog = 262144
net.core.somaxconn = 20480
net.core.optmem_max = 81920
# TCP conn
net.ipv4.tcp_max_syn_backlog = 262144
net.ipv4.tcp_syn_retries = 3
net.ipv4.tcp_retries1 = 3
net.ipv4.tcp_retries2 = 15
# tcp conn reuse
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_fin_timeout = 1
net.ipv4.tcp_max_tw_buckets = 20000
net.ipv4.tcp_max_orphans = 3276800
net.ipv4.tcp_timestamps = 1 #?
net.ipv4.tcp_synack_retries = 1
net.ipv4.tcp_syncookies = 1
# keepalive conn
net.ipv4.tcp_keepalive_time = 300
net.ipv4.tcp_keepalive_intvl = 30
net.ipv4.tcp_keepalive_probes = 3
net.ipv4.ip_local_port_range = 10001 65000
# swap
vm.overcommit_memory = 0
vm.swappiness = 10
#net.ipv4.conf.eth1.rp_filter = 0
#net.ipv4.conf.lo.arp_ignore = 1
#net.ipv4.conf.lo.arp_announce = 2
#net.ipv4.conf.all.arp_ignore = 1
#net.ipv4.conf.all.arp_announce = 2
EOF
echo -e "\e[32;1mKernel parameters modify complete\e[0m"
}
#9
modify_resource_limits () {
cat >> /etc/security/limits.conf <<EOF
* - core unlimited
* - nproc 1000000
* - nofile 1000000
* - memlock 32000
* - msgqueue 8192000
root - core unlimited
root - nproc 1000000
root - nofile 1000000
root - memlock 32000
root - msgqueue 8192000
EOF
echo -e "\e[32;1mResource limits modify complete\e[0m"
}
#10
set_software_source () {
if [[ $OS == CentOS-Linux-7* ]];then
mkdir /etc/yum.repos.d/backup && mv /etc/yum.repos.d/*.repo /etc/yum.repos.d/backup
curl -o /etc/yum.repos.d/Centos-7.repo https://mirrors.aliyun.com/repo/Centos-7.repo
curl -o /etc/yum.repos.d/epel-7.repo https://mirrors.aliyun.com/repo/epel-7.repo
yum clean all && yum makecache
elif [[ $OS == CentOS-Linux-8* ]];then
mkdir /etc/yum.repos.d/backup && mv /etc/yum.repos.d/*.repo /etc/yum.repos.d/backup
curl -o /etc/yum.repos.d/Centos-8.repo https://mirrors.aliyun.com/repo/Centos-8.repo
yum clean all && yum makecache
yum install -y https://mirrors.aliyun.com/epel/epel-release-latest-8.noarch.rpm
sed -i 's|^#baseurl=https://download.example/pub|baseurl=https://mirrors.aliyun.com|' /etc/yum.repos.d/epel*
sed -i 's|^metalink|#metalink|' /etc/yum.repos.d/epel*
elif [[ $OS == Ubuntu-18.04* ]];then
mkdir /etc/apt/backup && mv /etc/apt/sources.list /etc/apt/backup
cat > /etc/apt/sources.list <<EOF
deb http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse
EOF
rm -f /var/lib/apt/lists/lock && apt update
fi
echo -e "\e[32;1mSoftware source set complete\e[0m"
}
#11
install_package () {
if [[ $OS == CentOS-Linux-7* ]];then
yum install bash-completion vim-enhanced tree psmisc wget bc iotop gcc make gcc-c++ glibc glibc-devel pcre pcre-devel openssl openssl-devel zip unzip zlib-devel net-tools lrzsz ntpdate telnet lsof tcpdump libevent libevent-devel openssh-server openssh-clients postfix -y
elif [[ $OS == CentOS-Linux-8* ]];then
dnf install bash-completion vim-enhanced tree psmisc wget bc iotop gcc make gcc-c++ glibc glibc-devel pcre pcre-devel openssl openssl-devel zip unzip zlib-devel net-tools lrzsz chrony telnet lsof tcpdump libevent libevent-devel openssh-server openssh-clients postfix -y
elif [[ $OS == Ubuntu-18.04* ]];then
apt install make gcc iproute2 ntpdate tcpdump telnet traceroute nfs-kernel-server nfs-common lrzsz tree zip unzip openssl libssl-dev libpcre3 libpcre3-dev zlib1g-dev iotop libreadline-dev libsystemd-dev -y
fi
echo -e "\e[32;1mCommon Package already install\e[0m"
}
#12
set_time_sync () {
if [[ $OS == CentOS-Linux-7* ]];then
echo '*/5 * * * * ntpdate time1.aliyun.com &> /dev/null && hwclock -w' >> /var/spool/cron/root
systemctl restart crond
elif [[ $OS == CentOS-Linux-8* ]];then
sed -i.bak '/^pool /c pool time1.aliyun.com iburst' /etc/chrony.conf
systemctl restart chronyd && systemctl enable chronyd
echo '*/5 * * * * chronyc -a makestep &> /dev/null && hwclock -w' >> /var/spool/cron/root
systemctl restart crond
elif [[ $OS == Ubuntu-18.04* ]];then
echo '*/5 * * * * ntpdate time1.aliyun.com &> /dev/null && hwclock -w' >> /var/spool/cron/root
systemctl restart cron
fi
echo -e "\e[32;1mTime sync complete\e[0m"
}
#13
set_eth () {
if [[ $OS == CentOS* ]];then
sed -i.bak '/GRUB_CMDLINE_LINUX/s#"$# net.ifnames=0"#' /etc/default/grub
grub2-mkconfig -o /boot/grub2/grub.cfg &> /dev/null
elif [[ $OS == Ubuntu-18.04* ]];then
sed -i.bak '/GRUB_CMDLINE_LINUX/s#"$#net.ifnames=0"#' /etc/default/grub
grub-mkconfig -o /boot/grub/grub.cfg &> /dev/null
fi
echo -e "\e[32;1mNetname already modify,Restart to take effect\e[0m"
}
set_eth0 () {
if [[ $OS == Ubuntu-18.04* ]];then
mv /etc/netplan/01-netcfg.yaml{
,.bak}
cat > /etc/netplan/01-netcfg.yaml <<EOF
network:
version: 2
renderer: networkd
ethernets:
eth0:
dhcp4: no
addresses: [10.0.0.9/24]
gateway4: 10.0.0.2
nameservers:
addresses: [223.5.5.5,114.114.114.114]
EOF
fi
echo -e "\e[32;1mIP already set\e[0m"
}
#14
set_ip () {
if [[ $OS == CentOS-Linux-8* ]];then
mv /etc/sysconfig/network-scripts/ifcfg-ens160{
,.bak}
read -p "Please input IP: " IP
read -p "Please input Prefix: " PREFIX
read -p "Please input Gateway: " GATEWAY
read -p "Please input DNS1: " DNS1
read -p "Please input DNS2: " DNS2
cat > /etc/sysconfig/network-scripts/ifcfg-eth0 <<EOF
TYPE=Ethernet
NAME=eth0
DEVICE=eth0
BOOTPROTO=static
ONBOOT=yes
IPADDR=$IP
PREFIX=$PREFIX
GATEWAY=$GATEWAY
DNS1=$DNS1
DNS2=$DNS2
EOF
elif [[ $OS == CentOS-Linux-7* ]];then
mv /etc/sysconfig/network-scripts/ifcfg-ens33{
,.bak}
read -p "Please input IP: " IP
read -p "Please input Prefix: " PREFIX
read -p "Please input Gateway: " GATEWAY
read -p "Please input DNS1: " DNS1
read -p "Please input DNS2: " DNS2
cat > /etc/sysconfig/network-scripts/ifcfg-eth0 <<EOF
TYPE=Ethernet
NAME=eth0
DEVICE=eth0
BOOTPROTO=static
ONBOOT=yes
IPADDR=$IP
PREFIX=$PREFIX
GATEWAY=$GATEWAY
DNS1=$DNS1
DNS2=$DNS2
EOF
elif [[ $OS == Ubuntu-18.04* ]];then
mv /etc/netplan/01-netcfg.yaml{
,.bak}
read -p "Please input IP/PREFIX: " IP_MASK
read -p "Please input Gateway: " GATEWAY
read -p "Please input DNS: " DNS
cat > /etc/netplan/01-netcfg.yaml <<EOF
network:
version: 2
renderer: networkd
ethernets:
eth0:
dhcp4: no
addresses: [$IP_MASK]
gateway4: $GATEWAY
nameservers:
addresses: [$DNS]
EOF
fi
echo -e "\e[32;1mIP already set\e[0m"
}
echo -en "\e[32;1m"
cat <<EOF
This script applies to centos7 centos8 ubuntu1804!!!
Please select:
1)Perimtrootlogin
2)Disable SElinux
3)Disable Firewall
4)Modify PS1
5)Set default text editor
6)Modify vim
7)Set History
8)Modify kernel parameters
9)Modify resource limits
10)set_software_source
11)Install Common Package
12)Set Time Sync
13)Modify NetName
14)Set IP
15)All realized
EOF
echo -en '\e[0m'
read -p "Please input number 1-15: " MENU
case $MENU in
1)
set_ssh
;;
2)
disable_selinux
;;
3)
disbale_firewall
;;
4)
set_ps1
;;
5)
set_default_text_editor_vim
;;
6)
set_vim
;;
7)
set_history
;;
8)
modify_kernel_parameters
;;
9)
modify_resource_limits
;;
10)
set_software_source
;;
11)
install_package
;;
12)
set_time_sync
;;
13)
set_eth
set_eth0
;;
14)
set_ip
;;
15)
#set_ssh
disable_selinux
disbale_firewall
set_ps1
set_default_text_editor_vim
set_vim
set_history
modify_kernel_parameters
modify_resource_limits
set_software_source
install_package
set_time_sync
set_eth
set_eth0
#set_ip
echo -e "\e[32;1mAll done\e[0m"
;;
*)
echo -e "\e[32;1mINPUY FLASE!\e[0m"
;;
esac
Original link: Minimal installation system initialization script .