Linux 「运维命令」

Linux 阅读量

Linux 运维命令总结

查看某个端口进程

  • netstat
1
2
[root@caoxianliang ~]# netstat -tnlp | grep 80
tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN      17121/nginx: master
  • lsof
1
2
3
4
5
6
[root@caoxianliang ~]# lsof -i:80
COMMAND     PID USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
python     1175 root   17u  IPv4 930540      0t0  TCP caoxianliang:37217->36.110.220.15:http (ESTABLISHED)
AliYunDun 17050 root   19u  IPv4 926114      0t0  TCP caoxianliang:58918->106.11.68.13:http (ESTABLISHED)
nginx     17121 root    8u  IPv4 926506      0t0  TCP *:http (LISTEN)
nginx     17122  www    8u  IPv4 926506      0t0  TCP *:http (LISTEN)

删除0字节文件

1
find -type f -size 0 -exec rm -rf {} \;

查看进程

  • 按内存从大到小排列
1
ps -e -o "%C : %p : %z : %a" | sort -k5 -nr

按CPU利用率从大到小排列

1
ps -e -o "%C : %p : %z : %a" | sort -nr

查看HTTP的并发请求数及其TCP连接状态

1
netstat -n | awk '/^tcp/ {++S[$NF]} END {for(a in S) print a, S[a]}'

如何杀掉MYSQL进程

1
ps aux |grep mysql |grep -v grep  |awk '{print $2}' |xargs kill -9
1
killall -TERM mysqld
  • 查看mysql进程
1
service mysql status

显示运行3级别开启的服务

1
ls /etc/rc3.d/S* |cut -c 15-

查看内存的大小

1
free -m |grep "Mem" | awk '{print $2}'

统计一下服务器下面所有的jpg的文件的大小

1
find / -name *.jpg -exec wc -c {} \;|awk '{print $1}'|awk '{a+=$1}END{print a}'

查看CPU 负载

    1. cat /proc/loadavg
1
2
[root@caoxianliang ~]# cat /proc/loadavg
0.00 0.01 0.05 3/123 13560

检查前三个输出值是否超过了系统逻辑CPU的4倍。

    1. mpstat 1 1
1
2
3
4
5
6
[root@caoxianliang ~]# mpstat 1 1
Linux 3.10.0-862.3.2.el7.x86_64 (caoxianliang) 	07/23/2018 	_x86_64_	(1 CPU)

10:07:25 AM  CPU    %usr   %nice    %sys %iowait    %irq   %soft  %steal  %guest  %gnice   %idle
10:07:26 AM  all    0.00    0.00    0.00    0.00    0.00    0.00    0.00    0.00    0.00  100.00
Average:     all    0.00    0.00    0.00    0.00    0.00    0.00    0.00    0.00    0.00  100.00

检查%idle是否过低(比如小于5%)

找出占用空间最多的文件或目录

1
du -cks * | sort -rn | head -n 10
1
2
3
4
5
6
7
8
9
10
11
[root@caoxianliang ~]# du -cks * | sort -rn | head -n 10
669900	total
348556	bin
159544	lib
124740	mysql-test
30000	var
2800	sql-bench
2644	share
732	man
708	include
100	support-files

查看磁盘I/O负载

1
iostat -x 1 2
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
[root@caoxianliang ~]# iostat -x 1 2
Linux 3.10.0-862.3.2.el7.x86_64 (caoxianliang) 	07/23/2018 	_x86_64_	(1 CPU)

avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           0.20    0.01    0.11    0.02    0.00   99.65

Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s avgrq-sz avgqu-sz   await r_await w_await  svctm  %util
vda               0.00     0.34    0.09    0.77     1.49     5.37    15.97     0.00    5.54    7.19    5.35   0.33   0.03

avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           0.00    0.00    0.00    0.00    0.00  100.00

Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s avgrq-sz avgqu-sz   await r_await w_await  svctm  %util
vda               0.00     0.00    0.00    0.00     0.00     0.00     0.00     0.00    0.00    0.00    0.00   0.00   0.00

检查I/O使用率(%util)是否超过100%

查看网络负载

1
sar -n DEV
1
2
3
4
5
6
7
8
9
10
11
[root@caoxianliang ~]# sar -n DEV
Linux 3.10.0-862.3.2.el7.x86_64 (caoxianliang) 	07/23/2018 	_x86_64_	(1 CPU)

12:00:01 AM     IFACE   rxpck/s   txpck/s    rxkB/s    txkB/s   rxcmp/s   txcmp/s  rxmcst/s
12:10:01 AM      eth0      0.14      0.14      0.01      0.04      0.00      0.00      0.00
12:10:01 AM        lo      0.00      0.00      0.00      0.00      0.00      0.00      0.00
12:20:01 AM      eth0      0.08      0.10      0.00      0.01      0.00      0.00      0.00
12:20:01 AM        lo      0.00      0.00      0.00      0.00      0.00      0.00      0.00
12:30:01 AM      eth0      0.29      0.23      0.02      0.03      0.00      0.00      0.00
12:30:01 AM        lo      0.00      0.00      0.00      0.00      0.00      0.00      0.00
12:40:01 AM      eth0      0.26      0.17      0.02      0.02      0.00      0.00      0.00

检查网络流量(rxbyt/s, txbyt/s)是否过高

查看网络错误

1
2
3
4
5
[root@caoxianliang ~]# netstat -i
Kernel Interface table
Iface      MTU    RX-OK RX-ERR RX-DRP RX-OVR    TX-OK TX-ERR TX-DRP TX-OVR Flg
eth0      1500  1648927      0      0 0       1454542      0      0      0 BMRU
lo       65536      306      0      0 0           306      0      0      0 LRU

查看网络连接数目

1
2
3
4
5
6
[root@caoxianliang ~]# netstat -an | grep -E "^(tcp)" | cut -c 68- | sort | uniq -c | sort -n
      1  FIN_WAIT1  
      1  LAST_ACK   
      5  TIME_WAIT  
      6  ESTABLISHED
      6  LISTEN

查看进程总数

1
2
[root@caoxianliang ~]# ps aux | wc -l
74

检查进程个数是否正常 (比如超过250)

查看可运行进程数目

1
2
3
4
5
6
7
8
[root@caoxianliang ~]# vmstat 1 5
procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----
 r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st
 3  0      0 108564 135436 614224    0    0     2     5   41    7  0  0 100  0  0
 0  0      0 108564 135436 614224    0    0     0     0  118  179  1  0 99  0  0
 0  0      0 108564 135436 614224    0    0     0     0  128  189  0  0 100  0  0
 0  0      0 108564 135436 614224    0    0     0     0  138  208  0  0 100  0  0
 0  0      0 108564 135436 614224    0    0     0     0  128  187  0  1 99  0  0

列给出的是可运行进程的数目，检查其是否超过系统逻辑CPU的4倍

观察是否有异常进程出现

1
top -id 1

检查登录用户是否过多

  • uptime
1
2
[root@caoxianliang ~]# uptime
 11:01:15 up 9 days, 17:35,  1 user,  load average: 0.14, 0.14, 0.10
  • who |wc -l
1
2
[root@caoxianliang ~]# who | wc -l
1

查看系统时间

  • date
1
2
3
4
5
[root@caoxianliang ~]# date
Mon Jul 23 11:03:45 CST 2018

[root@caoxianliang ~]# date --date=yesterday
Sun Jul 22 11:34:21 CST 2018
  • cal
1
2
3
4
5
6
7
8
[root@caoxianliang ~]# cal
      July 2018     
Su Mo Tu We Th Fr Sa
 1  2  3  4  5  6  7
 8  9 10 11 12 13 14
15 16 17 18 19 20 21
22 23 24 25 26 27 28
29 30 31

检查打开文件总数是否过多

  • lsof |wc -l
1
2
[root@caoxianliang ~]# lsof | wc -l
3957

杀掉80端口相关的进程

1
lsof -i :80|grep -v "ID"|awk '{print "kill -9",$2}'|sh

使用 netstat -lntp 查看

tcpdump 抓包 ，用来防止80端口被人攻击时可以分析数据

1
tcpdump -c 10000 -i eth0 -n dst port 80 > /root/packets

实例:

1
2
3
4
5
6
[root@caoxianliang ~]# tcpdump -c 100 -i eth0 -n dst port 80 > /root/packets
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 262144 bytes
100 packets captured
101 packets received by filter
0 packets dropped by kernel

然后检查IP的重复数 并从小到大排序 注意 "-t\ +0" 中间是两个空格

1
less packets | awk {'printf $3"\n"'} | cut -d. -f 1-4 | sort | uniq -c | awk {'printf $1" "$2"\n"'} | sort -n -t\ +0

实例:

1
2
[root@caoxianliang ~]# less packets | awk {'printf $3"\n"'} | cut -d. -f 1-4 | sort | uniq -c | awk {'printf $1" "$2"\n"'} | sort -n 
100 172.31.45.94

查看有多少个活动的php-cgi进程

1
netstat -anp | grep php-cgi | grep ^tcp | wc -l

实例:

1
2
[root@caoxianliang ~]# netstat -anp | grep php-cgi | grep ^tcp | wc -l
0

查看系统自启动的服务

1
chkconfig --list | awk '{if ($5 == "3:on") print $1}'

实例:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
[root@caoxianliang ~]# chkconfig --list | awk '{if ($5=="3:on") print $1}'

Note: This output shows SysV services only and does not include native
      systemd services. SysV configuration data might be overridden by native
      systemd configuration.

      If you want to list systemd services use 'systemctl list-unit-files'.
      To see services enabled on particular target use
      'systemctl list-dependencies [target]'.

aegis
agentwatch
mysql
network
nginx
php-fpm
shadowsocks

查看硬件制作商

1
dmidecode -s system-product-name

实例:

1
2
[root@caoxianliang ~]# dmidecode -s system-product-name
Alibaba Cloud ECS

显示最常用的20条命令

1
cat ~/.bash_history |grep -v ^# |awk '{print $1}' |sort |uniq -c |sort -nr |head -20

实例:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
[root@caoxianliang ~]# cat .bash_history |grep -v ^# |awk '{print $1}' |sort |uniq -c |sort -nr |head -20
    265 ls
    200 cd
     43 vim
     28 rm
     28 ll
     28 cat
     24 rz
     24 ps
     15 yum
     15 uname
     14 rpm
     12 mkdir
     11 rar
     10 sh
     10 php
      9 whereis
      9 df
      9 chage
      8 tar
      8 curl

Powered by Hexo and Hexo-theme-hiker

Copyright © 2017 - 2023 Keep It Simple And Stupid All Rights Reserved.

访客数 : | 访问量 :