今天有几台服务器要上线，花时间写了一个初始化的脚本，跟大家分享一下。欢迎大家提意见，帮助我让其功能更加完善

#!/bin/bash
# author: gm100861
# mail: [email protected]
# blog: http://www.gm100861.com
# date: 2013-06-25
if [ $(id -u) != 0 ];then
echo "Must be root can do this."
exit 9
fi
# set privileges
chmod 600 /etc/passwd
chmod 600 /etc/shadow
chmod 600 /etc/group
chmod 600 /etc/gshadow
echo "Set important files privileges sucessfully"
# yum repo add
cat > /etc/yum.repos.d/thrid-repository.repo </dev/null
yum makecache &>/dev/null
echo "add thired repository sucessfully"
# Turn off unnecessary services
service=($(ls /etc/init.d/))
for i in ${service[@]}; do
case $i in
sshd|network|syslog|iptables|crond)
chkconfig $i on;;
*)
chkconfig $i off;;
esac
done
#set ulimit
cat >> /etc/security/limits.conf << EOF
* soft nofile 65535
* hard nofile 65535
EOF
# set sysctl
cat > /etc/sysctl.conf << EOF
net.ipv4.ip_forward = 0
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.default.accept_source_route = 0
kernel.sysrq = 0
kernel.core_uses_pid = 1
kernel.msgmnb = 65536
kernel.msgmax = 65536
kernel.shmmax = 68719476736
kernel.shmall = 4294967296
net.ipv4.tcp_max_tw_buckets = 6000
net.ipv4.tcp_sack = 1
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_rmem = 4096 87380 4194304
net.ipv4.tcp_wmem = 4096 16384 4194304
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 = 262144
net.ipv4.tcp_max_orphans = 3276800
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_max_syn_backlog = 262144
net.ipv4.tcp_timestamps = 0
net.ipv4.tcp_synack_retries = 1
net.ipv4.tcp_syn_retries = 1
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_mem = 94500000 915000000 927000000
net.ipv4.tcp_fin_timeout = 1
net.ipv4.tcp_keepalive_time = 1200
net.ipv4.ip_local_port_range = 1024 65535
vm.swappiness = 0
EOF
echo "0 0 * * * /usr/sbin/ntpdate cn.pool.ntp.org &>/dev/null" >>/var/spool/cron/root
# set iptables
iptables -F
iptables -X
iptables -Z
iptables -I INPUT -i lo -j ACCEPT
iptables -A INPUT -p tcp --dport 22 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j ACCEPT
iptables -A INPUT -p icmp --icmp-type 0 -m limit --limit 3/second --limit-burst 5 -j ACCEPT
iptables -A INPUT -p icmp --icmp-type 8 -m limit --limit 3/second --limit-burst 5 -j ACCEPT
iptables -A INPUT -p udp --sport 53 -j ACCEPT
iptables -A INPUT -p tcp --sport 53 -j ACCEPT
iptables -P INPUT DROP
#iptables -P FORWARD DROP
#iptables -P OUTPUT DROP
/etc/init.d/iptables save
echo "All things is init ok! "