linux一些命令备忘

• 拒绝多次登录失败的人继续登录
• 逻辑删除,防止误操作
• 清理所有操作痕迹
• 一键安装v2

拒绝多次登录失败的人继续登录#

#!/usr/bin/bash
# -*- coding:UTF-8 -*-
#
#########################################################
#                                                       #
#    file name: ssh_login_failed_host_deny              #
#  description: 将SSH多次登录失败的IP加入黑名单         #
#########################################################


# 通过lastb获取登录失败的IP及登录失败的次数
lastb | awk '{print $3}' | grep ^[0-9] | sort | uniq -c | awk '{print $1"\t"$2}' > /tmp/host_list
list=`cat /tmp/host_list`
line=`wc -l /tmp/host_list | awk '{print $1}'`
count=1

# 如果/tmp/host_list中有数据，循环至少需要执行一次
while [[ "$line" -ge "$count" ]]; do
	ip_add=`echo $list | awk '{FS="\t"} {print $2}'`
	num=`echo $list | awk  '{FS="\t"} {print $1}'`
#   登录失败达到5次就将该IP写入文件
	if [[ "$num" -ge 5 ]]; then
		grep "$ip_add" /etc/hosts.deny &> /dev/null
		if [[ "$?" -gt 0 ]]; then
# --------> 此处添加当前系统时间，请根据实际情况定义日期格式
			echo "# $(date +%F' '%H:%M:%S)" >> /etc/hosts.deny
			echo "sshd:$ip_add" >> /etc/hosts.deny
		fi
	fi
	let count+=1
#   删除已经写入文件的IP
	sed -i '1d' /tmp/host_list
#   修改$list变量
	list=`cat /tmp/host_list`
done
# 清空临时文件
echo '' > /tmp/host_list
exit 0

逻辑删除,防止误操作#

先准备目录:mkdir -p /main/.rm_trash/files

下面文件rm.sh放到/main/.rm_trash/目录下:

#!/bin/bash
PARA_CNT=$#
# 逻辑删除存档地
TRASH_DIR="/main/.rm_trash/files"
 
for i in $*; do
	if [[ "$i" == "-rf"  ]];then
		continue
	elif [[ "$i" == "-r" ]];then
		continue
	fi
	#echo "参数 $i"
	STAMP=`date -d today +"%Y-%m-%d-%T"`
	fileName=`basename $i`
	first_char="${i:0:1}"
    #echo $first_char
    if [[ "$first_char" == "/" ]];then
	    echo "["$STAMP"] del $fileName  from "$i >> $TRASH_DIR/../rm.log
    else
	    echo "["$STAMP"] del $fileName  from "`pwd`"/"$i >> $TRASH_DIR/../rm.log
    fi
    mv $i $TRASH_DIR/$fileName.$STAMP
done

然后在/etc/bash.bashrc中加上:

# 修改rm命令为mv命令
alias rm="bash /main/.rm_trash/rm.sh"

清理所有操作痕迹#

cat /dev/null > /var/log/wtmp
cat /dev/null > /var/log/btmp
cat /dev/null > /var/log/lastlog
cat /dev/null > /var/log/secure
cat /dev/null > /var/log/messages
cat /dev/null > /var/log/syslog
cat /dev/null > /var/log/tallylog
rm -rf /var/log/messages-*
rm -rf /var/log/secure-*
rm -rf /var/log/wtmp.*
rm -rf /var/log/syslog.*
rm -rf /var/log/kern.log.*
rm -rf /var/log/dpkg.log.*
rm -rf /var/log/auth.log.*
rm -rf /var/log/alternatives.log.*
history -c
history -w

一键安装v2#

bash <(curl -s -L https://git.io/v2ray.sh)

# https://raw.githubusercontent.com/233boy/v2ray/master/install.sh