9 个实用 shell 脚本，建议收藏！

1. Dos 攻击防范（自动屏蔽攻击 IP）

#!/bin/bashDATE=$(date +%d/%b/%Y:%H:%M)LOG_FILE=/usr/local/nginx/logs/demo2.access.logABNORMAL_IP=$(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    fidone

2. Linux 系统发送告警脚本

# yum install mailx# vi /etc/mail.rcset from=baojingtongzhi@163.com smtp=smtp.163.comset smtp-auth-user=baojingtongzhi@163.com smtp-auth-password=123456set smtp-auth=login

3. MySQL 数据库备份单循环

#!/bin/bashDATE=$(date +%F_%H-%M-%S)HOST=localhostUSER=backupPASS=123.comBACKUP_DIR=/data/db_backupDB_LIST=$(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!"    fidone

4. MySQL 数据库备份多循环

#!/bin/bashDATE=$(date +%F_%H-%M-%S)HOST=localhostUSER=backupPASS=123.comBACKUP_DIR=/data/db_backupDB_LIST=$(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}    [ ! -d $BACKUP_DB_DIR ] && mkdir -p $BACKUP_DB_DIR &>/dev/null    TABLE_LIST=$(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/${TABLE}.sql        if ! mysqldump -h$HOST -u$USER -p$PASS $DB $TABLE > $BACKUP_NAME 2>/dev/null; then            echo "$BACKUP_NAME 备份失败!"        fi    donedone

5. Nginx 访问访问日志按天切割 关注Linux中文社区

#!/bin/bashLOG_DIR=/usr/local/nginx/logsYESTERDAY_TIME=$(date -d "yesterday" +%F)LOG_MONTH_DIR=$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    mv $LOG_DIR/$LOG_FILE $LOG_MONTH_DIR/${LOG_FILE}_${YESTERDAY_TIME}donekill -USR1 $(cat /var/run/nginx.pid)

6. Nginx 访问日志分析脚本

#!/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=$1echo "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 -10echo "----------------------"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 -10echo "----------------------"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 -nrecho "----------------------"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]}}'

7. 查看网卡实时流量脚本

#!/bin/bashNIC=$1echo -e " In ------ Out"while true; do    OLD_IN=$(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 1done

8. 服务器系统配置初始化脚本 另外，搜索公众号Linux就该这样学后台回复“Linux”，获取一份惊喜礼包。

#/bin/bash# 设置时区并同步时间ln -s /usr/share/zoneinfo/Asia/Shanghai /etc/localtimeif ! crontab -l |grep ntpdate &>/dev/null ; then    (echo "* 1 * * * ntpdate time.windows.com >/dev/null 2>&1";crontab -l) |crontabfi# 禁用selinuxsed -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 firewalldelif egrep "6.[0-9]" /etc/redhat-release &>/dev/null; then    service iptables stop    chkconfig iptables offfi# 历史命令显示操作时间if ! grep HISTTIMEFORMAT /etc/bashrc; then    echo 'export HISTTIMEFORMAT="%F %T `whoami` "' >> /etc/bashrcfi# SSH超时时间if ! grep "TMOUT=600" /etc/profile &>/dev/null; then    echo "export TMOUT=600" >> /etc/profilefi# 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 65535EOFfi# 系统内核优化cat >> /etc/sysctl.conf << EOFnet.ipv4.tcp_syncookies = 1net.ipv4.tcp_max_tw_buckets = 20480net.ipv4.tcp_max_syn_backlog = 20480net.core.netdev_max_backlog = 262144net.ipv4.tcp_fin_timeout = 20EOF# 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 if

9. 监控 100 台服务器磁盘利用率脚本

#!/bin/bashHOST_INFO=host.infofor IP in $(awk '/^[^#]/{print $1}' $HOST_INFO); do    USER=$(awk -v ip=$IP 'ip==$1{print $2}' $HOST_INFO)    PORT=$(awk -v ip=$IP 'ip==$1{print $3}' $HOST_INFO)    TMP_FILE=/tmp/disk.tmp    ssh -p $PORT $USER@$IP 'df -h' > $TMP_FILE    USE_RATE_LIST=$(awk 'BEGIN{OFS="="}/^\/dev/{print $NF,int($5)}' $TMP_FILE)    for USE_RATE in $USE_RATE_LIST; do        PART_NAME=${USE_RATE%=*}        USE_RATE=${USE_RATE#*=}        if [ $USE_RATE -ge 80 ]; then            echo "Warning: $PART_NAME Partition usage $USE_RATE%!"        fi    donedone