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服务器系统配置初始化
#/bin/bash
# 安装系统性能分析工具及其他
yum install gcc make autoconf vim sysstat net-tools iostat iftop iotp wget lrzsz lsof unzip openssh-clients net-tool vim ntpdate -y
# 设置时区并同步时间
ln -s /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
if ! crontab -l |grep ntpdate &>/dev/null ; then
(echo "* 1 * * * ntpdate time.windows.com >/dev/null 2>&1";crontab -l) |crontab
fi
# 禁用selinux
sed -i '/SELINUX/{s/permissive/disabled/}' /etc/selinux/config
# 关闭防火墙
if egrep "7.[0-9]" /etc/redhat-release &>/dev/null; then
systemctl stop firewalld
systemctl disable firewalld
elif egrep "6.[0-9]" /etc/redhat-release &>/dev/null; then
service iptables stop
chkconfig iptables off
fi
# 历史命令显示操作时间
if ! grep HISTTIMEFORMAT /etc/bashrc; then
echo 'export HISTTIMEFORMAT="%Y-%m-%d %H:%M:%S `whoami` "' >> /etc/bashrc
fi
# SSH超时时间
if ! grep "TMOUT=600" /etc/profile &>/dev/null; then
echo "export TMOUT=600" >> /etc/profile
fi
# 禁止root远程登录 切记给系统添加普通用户,给su到root的权限
sed -i 's/#PermitRootLogin yes/PermitRootLogin no/' /etc/ssh/sshd_config
# 禁止定时任务向发送邮件
sed -i 's/^MAILTO=root/MAILTO=""/' /etc/crontab
# 设置最大打开文件数
if ! grep "* soft nofile 65535" /etc/security/limits.conf &>/dev/null; then
cat >> /etc/security/limits.conf << EOF
* soft nofile 65535
* hard nofile 65535
EOF
fi
# 系统内核优化
cat >> /etc/sysctl.conf << EOF
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_max_tw_buckets = 20480
net.ipv4.tcp_max_syn_backlog = 20480
net.core.netdev_max_backlog = 262144
net.ipv4.tcp_fin_timeout = 20
EOF
# 减少SWAP使用
echo "0" > /proc/sys/vm/swappiness
批量创建多个用户并设置密码
#!/bin/bash
USER_LIST=$@
USER_FILE=./user.info
for USER in $USER_LIST;do
if ! id $USER &>/dev/null; then
PASS=$(echo $RANDOM |md5sum |cut -c 1-8)
useradd $USER
echo $PASS | passwd --stdin $USER &>/dev/null
echo "$USER $PASS" >> $USER_FILE
echo "$USER User create successful."
else
echo "$USER User already exists!"
fi
done
一键查看服务器利用率
#!/bin/bash
function cpu(){
util=$(vmstat | awk '{if(NR==3)print $13+$14}')
iowait=$(vmstat | awk '{if(NR==3)print $16}')
echo "CPU -使用率:${util}% ,等待磁盘IO相应使用率:${iowait}:${iowait}%"
}
function memory (){
total=`free -m |awk '{if(NR==2)printf "%.1f",$2/1024}'`
used=`free -m |awk '{if(NR==2) printf "%.1f",($2-$NF)/1024}'`
available=`free -m |awk '{if(NR==2) printf "%.1f",$NF/1024}'`
echo "内存 - 总大小: ${total}G , 使用: ${used}G , 剩余: ${available}G"
}
disk(){
fs=$(df -h |awk '/^\/dev/{print $1}')
for p in $fs; do
mounted=$(df -h |awk '$1=="'$p'"{print $NF}')
size=$(df -h |awk '$1=="'$p'"{print $2}')
used=$(df -h |awk '$1=="'$p'"{print $3}')
used_percent=$(df -h |awk '$1=="'$p'"{print $5}')
echo "硬盘 - 挂载点: $mounted , 总大小: $size , 使用: $used , 使用率: $used_percent"
done
}
function tcp_status() {
summary=$(ss -antp |awk '{status[$1]++}END{for(i in status) printf i":"status[i]" "}')
echo "TCP连接状态 - $summary"
}
cpu
memory
disk
tcp_status
查看网卡的实时流量
#!/bin/bash
eth0=$1
echo -e "流量进入--流量传出 "
while true; do
old_in=$(cat /proc/net/dev |grep $eth0 |awk '{print $2}')
old_out=$(cat /proc/net/dev |grep $eth0 |awk '{print $10}')
sleep 1
new_in=$(cat /proc/net/dev |grep $eth0 |awk '{print $2}')
new_out=$(cat /proc/net/dev |grep $eth0 |awk '{print $10}')
in=$(printf "%.1f%s" "$((($new_in-$old_in)/1024))" "KB/s")
out=$(printf "%.1f%s" "$((($new_out-$old_out)/1024))" "KB/s")
echo "$in $out"
done