本文共 3038 字，大约阅读时间需要 10 分钟。
系统网络连接状态：
1.查看TCP连接状态
| 1 2 3 4 5 6 | netstat -nat | awk ‘{print $6}’| sort | uniq -c| sort -rn netstat -n | awk ‘/^tcp/ {++S[$NF]};END { for (a in S) print a, S[a]}’ 或 netstat -n | awk ‘/^tcp/ {++state[$NF]}; END { for (key in state) print key, "\t" ,state[key]}’ netstat -n | awk ‘/^tcp/ {++arr[$NF]};END { for (k in arr) print k, "t" ,arr[k]}’ netstat -n | awk ‘/^tcp/ {print $NF}’| sort | uniq -c| sort -rn netstat -ant | awk ‘{print $NF}’ | grep - v ‘[a-z]‘ | sort | uniq -c |
2.查找请求数请20个IP（常用于查找攻来源）：
| 1 2 | netstat -anlp| grep 80| grep tcp| awk ‘{print $5}’| awk -F: ‘{print $1}’| sort | uniq -c| sort -nr| head -n20 netstat -ant | awk ‘/:80/{ split ($5,ip, ":" );++A[ip[1]]}END{ for (i in A) print A[i],i}’ | sort -rn| head -n20 |
3.用tcpdump嗅探80端口的访问看看谁最高
| 1 | tcpdump -i eth0 -tnn dst port 80 -c 1000 | awk -F "." ‘{print $1 "." $2 "." $3 "." $4}’ | sort | uniq -c | sort -nr | head -20 |
4.查找较多time_wait连接
| 1 | netstat -n| grep TIME_WAIT| awk ‘{print $5}’| sort | uniq -c| sort -rn| head -n20 |
5.找查较多的SYN连接
| 1 | netstat -an | grep SYN | awk ‘{print $5}’ | awk -F: ‘{print $1}’ | sort | uniq -c | sort -nr | more |
6.根据端口列进程
| 1 | netstat -ntlp | grep 80 | awk ‘{print $7}’ | cut -d/ -f1 |
网站日志分析（Apache）：
1.获得访问前10位的ip地址
| 1 2 | cat access.log| awk ‘{print $1}’| sort | uniq -c| sort -nr| head -10 cat access.log| awk ‘{counts[$(11)]+=1}; END { for (url in counts) print counts[url], url}’ |
2.访问次数最多的文件或页面,取前20
| 1 | cat access.log| awk ‘{print $11}’| sort | uniq -c| sort -nr| head -20 |
3.列出传输最大的几个exe文件（分析下载站的时候常用）
| 1 | cat access.log | awk ‘($7~/.exe/){print $10 " " $1 " " $4 " " $7}’| sort -nr| head -20 |
4.列出输出大于200000byte(约200kb)的exe文件以及对应文件发生次数
| 1 | cat access.log | awk ‘($10 > 200000 && $7~/.exe/){print $7}’| sort -n| uniq -c| sort -nr| head -100 |
5.如果日志最后一列记录的是页面文件传输时间，则有列出到客户端最耗时的页面
| 1 | cat access.log | awk ‘($7~/.php/){print $NF " " $1 " " $4 " " $7}’| sort -nr| head -100 |
6.列出最最耗时的页面(超过60秒的)的以及对应页面发生次数
| 1 | cat access.log | awk ‘($NF > 60 && $7~/.php/){print $7}’| sort -n| uniq -c| sort -nr| head -100 |
7.列出传输时间超过 30 秒的文件
| 1 | cat access.log | awk ‘($NF > 30){print $7}’| sort -n| uniq -c| sort -nr| head -20 |
8.统计网站流量（G)
| 1 | cat access.log | awk ‘{ sum +=$10} END {print sum /1024/1024/1024 }’ |
9.统计404的连接
| 1 | awk ‘($9 ~ /404/ )’ access.log | awk ‘{print $9,$7}’ | sort |
10. 统计http status
| 1 2 | cat access.log | awk ‘{counts[$(9)]+=1}; END { for (code in counts) print code, counts[code]}' cat access.log | awk '{print $9}' | sort | uniq -c| sort -rn |
10.蜘蛛分析，查看是哪些蜘蛛在抓取内容。
| 1 | /usr/sbin/tcpdump -i eth0 -l -s 0 -w - dst port 80 | strings | grep -i user-agent | grep -i -E 'bot|crawler|slurp|spider' |
网站日志分析2(Squid）按域统计流量
| 1 | zcat squid_access.log. tar .gz| awk '{print $10,$7}' | awk 'BEGIN{FS="[ /]"}{trfc[$4]+=$1}END{for(domain in trfc){printf "%st%dn",domain,trfc[domain]}}' |
数据库：
1.查看数据库执行的sql
| 1 | /usr/sbin/tcpdump -i eth0 -s 0 -l -w - dst port 3306 | strings | egrep -i 'SELECT|UPDATE|DELETE|INSERT|SET|COMMIT|ROLLBACK|CREATE|DROP|ALTER|CALL' |
系统Debug分析：
1.调试命令
| 1 | strace -p pid |
2.跟踪指定进程的PID
| 1 | gdb -p pid |