Shell script notes-1

Dos attack prevention (automatically shield attack IP)

#!/bin/bash
DATE=$(date +%d/%b/%Y:%H:%M)
LOG_FILE=/usr/local/nginx/logs/demo2.access.log
ABNORMAL_IP=$(tail -n5000 $LOG_FILE |grep $DATE |awk '{
     
     a[$1]++}END{
     
     for(i in a)if(a[i]>10)print i}')
for IP in $ABNORMAL_IP; do
    if [ $(iptables -vnL |grep -c "$IP") -eq 0 ]; then
        iptables -I INPUT -s $IP -j DROP
        echo "$(date +'%F_%T') $IP" >> /tmp/drop_ip.log
    fi
done

# date +%d/%b/%Y:%H:%M 输出结果 22/Sep/2020:10:27
#NGINX 日志access.log日志内容：
#192.168.26.131 - - [14/Aug/2020:09:43:45 +0800] "GET / HTTP/1.1" 302 145 "-" "-"
#192.168.26.1 - - [30/Apr/2020:11:57:25 +0800] "GET /uploads/home/adv/5a43558d3d004.jpg HTTP/1.1" 200 20351 "http://www.shop1.com/index.php" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.122 Safari/537.36"

#ABNORMAL_IP 查看访问日志的后5000行，筛选当前时间，awk循环， $1自增，如果超过10，则打印出来
#循环遍历ABNORMAL_IP， 与防火墙里面内容匹配次数，如果等于0，则封IP/drop ip

Linux system sends alarm script

# yum install mailx
# vi /etc/mail.rc    设置发邮件的邮箱，
set from=[email protected] smtp=smtp.163.com
set smtp-auth-user=[email protected] smtp-auth-password=123456
set smtp-auth=login

#set [email protected]
#set smtp=smtp.qq.com
#set [email protected]
#set smtp-auth-password=bfzxlaahcsxxxxxj

MySQL database backup single cycle

#!/bin/bash 
DATE=$(date +%F_%H-%M-%S)
HOST=localhost
USER=backup
PASS=123.com
BACKUP_DIR=/data/db_backup
DB_LIST=$(mysql -h$HOST -u$USER -p$PASS -s -e "show databases;" 2>/dev/null |egrep -v "Database|information_schema|mysql|performance_schema|sys")

for DB in $DB_LIST; do
    BACKUP_NAME=$BACKUP_DIR/${DB}_${DATE}.sql
    if ! mysqldump -h$HOST -u$USER -p$PASS -B $DB > $BACKUP_NAME 2>/dev/null; then
        echo "$BACKUP_NAME 备份失败!"
    fi
done

#分库备份
# date +%F_%H-%M-%S 输出结果 2020-09-22_11-00-31
#DB_LIST 为 -s静默模式， -e 执行sql指令， 2>/dev/null不显示系统提示。egrep -v 反向筛选。 
#结果为： ds_shop test  只有一行

#  BACKUP_NAME 结果是  /data/db_backup/ds_shop_2020-09-22_11-15-09.sql
#  -B 数据库 > sql文件
#  说明：加了-B参数后，备份文件中多的Create database和use mytest的命令
#加-B参数的好处：导出的数据文件中已存在创建库和使用库的语句，不需要手动在原库是创建库的操作，
#在恢复过程中不需要手动建库，可以直接还原恢复。
# 另一种备份mysqldump -uroot -pa123456 ds_shop > ds_shop.sql

MySQL database backup multi-cycle

#!/bin/bash
DATE=$(date +%F_%H-%M-%S)
HOST=localhost
USER=backup
PASS=123.com
BACKUP_DIR=/data/db_backup
DB_LIST=$(mysql -h$HOST -u$USER -p$PASS -s -e "show databases;" 2>/dev/null |egrep -v "Database|information_schema|mysql|performance_schema|sys")

for DB in $DB_LIST; do
    BACKUP_DB_DIR=$BACKUP_DIR/${DB}_${DATE}
    #如果不存在则创建
    [ ! -d $BACKUP_DB_DIR ] && mkdir -p $BACKUP_DB_DIR &>/dev/null
    #TABLE_LIST 查询当前库的表信息
    TABLE_LIST=$(mysql -h$HOST -u$USER -p$PASS -s -e "use $DB;show tables;" 2>/dev/null)
    for TABLE in $TABLE_LIST; do
        BACKUP_NAME=$BACKUP_DB_DIR/${TABLE}.sql 
        #保存表的sql
        #加了参数的写法（效果一样）：mysqldump -uroot -pa123456 -B ds_shop --table ds_wxconfig > ds_wxconfig2.sql
        if ! mysqldump -h$HOST -u$USER -p$PASS $DB $TABLE > $BACKUP_NAME 2>/dev/null; then
            echo "$BACKUP_NAME 备份失败!"
        fi
    done
done
# 分表备份
# date +%F_%H-%M-%S 2020-09-22_11-43-06
# DB_LIST 查出当前数据库信息
# 

nginx access logs are cut by day

#!/bin/bash
LOG_DIR=/usr/local/nginx/logs
#获取到上一天的时间
YESTERDAY_TIME=$(date -d "yesterday" +%F)
#归档日志取时间
LOG_MONTH_DIR=$LOG_DIR/$(date +"%Y-%m")
LOG_FILE_LIST="default.access.log"

for LOG_FILE in $LOG_FILE_LIST; do
    [ ! -d $LOG_MONTH_DIR ] && mkdir -p $LOG_MONTH_DIR
    # 如文件夹2020-01 里面存放的是每天的日志
    mv $LOG_DIR/$LOG_FILE $LOG_MONTH_DIR/${LOG_FILE}_${YESTERDAY_TIME}
done

kill -USR1 $(cat /var/run/nginx.pid)


# $(date -d "yesterday" +%F) 输出结果 2020-09-21
# date +"%Y-%m" 结果 2020-09


#kill -USR1 USR1亦通常被用来告知应用程序重载配置文件；
#例如，向Apache HTTP服务器发送一个USR1信号将导致以下步骤的发生：停止接受新的连接，等待当前连接停止，
#重新载入配置文件，重新打开日志文件，重启服务器，从而实现相对平滑的不关机的更改。

Nginx access log analysis script

#!/bin/bash
# 日志格式: $remote_addr - $remote_user [$time_local] "$request" $status $body_bytes_sent "$http_referer" "$http_user_agent" "$http_x_forwarded_for"
LOG_FILE=$1
echo "统计访问最多的10个IP"
awk '{a[$1]++}END{print "UV:",length(a);for(v in a)print v,a[v]}' $LOG_FILE |sort -k2 -nr |head -10
echo "----------------------"
#192.168.26.1 2197
#192.168.26.131 16
#192.168.26.130 8
#127.0.0.1 6
#UV: 4

#awk 自带时间范围筛选
echo "统计时间段访问最多的IP"
awk '$4>="[01/Dec/2018:13:20:25" && $4<="[27/Nov/2018:16:20:49"{a[$1]++}END{for(v in a)print v,a[v]}' $LOG_FILE |sort -k2 -nr|head -10
echo "----------------------"


echo "统计访问最多的10个页面"
awk '{a[$7]++}END{print "PV:",length(a);for(v in a){if(a[v]>10)print v,a[v]}}' $LOG_FILE |sort -k2 -nr
echo "----------------------"

echo "统计访问页面状态码数量"
awk '{a[$7" "$9]++}END{for(v in a){if(a[v]>5)print v,a[v]}}' $LOG_FILE |sort -k3 -nr

View the real-time traffic script of the network card

#!/bin/bash
NIC=$1
echo -e " In ------ Out"
while true; do
    OLD_IN=$(awk '$0~"'$NIC'"{print $2}' /proc/net/dev)
    OLD_OUT=$(awk '$0~"'$NIC'"{print $10}' /proc/net/dev)
    sleep 1
    NEW_IN=$(awk  '$0~"'$NIC'"{print $2}' /proc/net/dev)
    NEW_OUT=$(awk '$0~"'$NIC'"{print $10}' /proc/net/dev)
    IN=$(printf "%.1f%s" "$((($NEW_IN-$OLD_IN)/1024))" "KB/s")
    OUT=$(printf "%.1f%s" "$((($NEW_OUT-$OLD_OUT)/1024))" "KB/s")
    echo "$IN $OUT"
    sleep 1
done


#用法 bash e.sh ens192
# $0 匹配 $NIC的值 则输出 $2 ,$10

Server system configuration initialization script

#/bin/bash
# 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="%F %T `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
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

# 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 lrzsz -y

The content of the script refers to the information on the Internet; do the analysis and experiment test by yourself.

Reference blog: https://blog.csdn.net/heian_99/category_9675115.html

Ara

Part 1 - END