Linux笔记03（经常使用命令）

时间 2021-08-12

标签 node linux redis shell 数据库安全 bash markdown 网络架构栏目 Linux 繁體版

原文原文链接

本次主要仍是弄一些基础命令……node

一、系统状态检测命令

一、ifconifg

查看网卡信息linux

[root@mingmingxingforcomputer ~]# ifconfig 
ens160: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.0.15  netmask 255.255.255.0  broadcast 192.168.0.255
        inet6 fe80::3928:f622:d292:1173  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:ba:95:53  txqueuelen 1000  (Ethernet)
        RX packets 61  bytes 8494 (8.2 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 58  bytes 8801 (8.5 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 48  bytes 5616 (5.4 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 48  bytes 5616 (5.4 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

virbr0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        inet 192.168.122.1  netmask 255.255.255.0  broadcast 192.168.122.255
        ether 52:54:00:a0:0a:88  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

参数	描述
ens160	网卡名称
inet 192.168.0.15	IP地址
netmask 255.255.255.0	子网掩码
ether 00:0c:29:ba:95:53	物理地址

二、uname

查看系统信息redis

[root@mingmingxingforcomputer ~]# uname 
Linux
[root@mingmingxingforcomputer ~]# uname -a
Linux mingmingxingforcomputer 4.18.0-80.el8.x86_64 #1 SMP Wed Mar 13 12:02:46 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

三、uptime

查看系统的负载信息 shell

[root@mingmingxingforcomputer ~]# uptime
 15:03:53 up 9 min,  1 user,  load average: 0.00, 0.11, 0.12

负载值越低越好指的是对运维人员来说的，越低越安全省心。可是公司购置的硬件设备若是长期处于空闲状态，明显是种资源浪费，老板也不会开心。因此咱们建议是负载值保持在1左右，不要超过5就好。数据库

四、free

用于显示当前系统中内存的使用量信息 安全

[root@mingmingxingforcomputer ~]# free 
              total        used        free      shared  buff/cache   available
Mem:        7977588      767364     6767808        9880      442416     6939484
Swap:       2097148           0     2097148
// -h 参数能够更加直观的看到内存使用状况
[root@mingmingxingforcomputer ~]# free -h
              total        used        free      shared  buff/cache   available
Mem:          7.6Gi       749Mi       6.5Gi       9.0Mi       432Mi       6.6Gi
Swap:         2.0Gi          0B       2.0Gi

五、who

查看当前登入主机的用户终端信息 bash

[root@mingmingxingforcomputer ~]# who
root     pts/0        2021-06-26 14:55 (192.168.0.9)

六、last

用于调取主机的被访记录 markdown

[root@mingmingxingforcomputer ~]# last
root     pts/0        192.168.0.9      Sat Jun 26 14:55   still logged in
reboot   system boot  4.18.0-80.el8.x8 Fri Jun 25 01:16   still running
root     pts/1        192.168.0.9      Sat Jun 26 21:25 - 14:53  (-6:32)
root     tty2         tty2             Sat Jun 26 18:33 - down   (-3:40)
reboot   system boot  4.18.0-80.el8.x8 Sat Jun 26 18:20 - 14:53  (-3:26)
root     tty2         tty2             Sat Jun 26 05:30 - 07:01  (01:30)
reboot   system boot  4.18.0-80.el8.x8 Sat Jun 26 04:51 - 07:01  (02:10)
root     pts/2        192.168.0.2      Thu Jan 21 21:24 - 21:39  (00:15)
root     pts/2        192.168.0.2      Wed Jan 20 05:28 - 05:29  (00:00)
root     pts/1        192.168.0.2      Wed Jan 20 05:25 - 21:39 (1+16:14)
root     pts/1        192.168.0.2      Wed Jan 20 05:24 - 05:25  (00:00)
root     tty2         tty2             Wed Jan 20 05:20 - 21:39 (1+16:19)
reboot   system boot  4.18.0-80.el8.x8 Wed Jan 20 05:20 - 21:40 (1+16:19)
root     tty2         tty2             Wed Jan 20 05:00 - 05:17  (00:17)
reboot   system boot  4.18.0-80.el8.x8 Wed Jan 20 05:00 - 05:17  (00:17)
reboot   system boot  4.18.0-80.el8.x8 Wed Jan 20 04:59 - 05:17  (00:17)
root     tty2         tty2             Wed Jan 20 04:44 - down   (00:14)
reboot   system boot  4.18.0-80.el8.x8 Wed Jan 20 04:44 - 04:59  (00:15)
root     tty2         tty2             Mon Jan  4 03:40 - 04:52  (01:11)
reboot   system boot  4.18.0-80.el8.x8 Mon Jan  4 03:37 - 04:52  (01:14)

wtmp begins Mon Jan  4 03:37:53 2021

七、ping

控制ping次数【-c】网络

[root@mingmingxingforcomputer ~]# ping -c 3 192.168.0.1
PING 192.168.0.1 (192.168.0.1) 56(84) bytes of data.
64 bytes from 192.168.0.1: icmp_seq=1 ttl=64 time=0.601 ms
64 bytes from 192.168.0.1: icmp_seq=2 ttl=64 time=6.33 ms
64 bytes from 192.168.0.1: icmp_seq=3 ttl=64 time=1.15 ms

--- 192.168.0.1 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 28ms
rtt min/avg/max/mdev = 0.601/2.693/6.332/2.582 ms

参数	做用
-c	总共发送次数
-l	指定网卡名称
-i	每次间隔时间（秒）
-W	最长等待时间（秒）

八、tracepath

显示数据包达到目的主机途中所通过的路由信息 架构

[root@mingmingxingforcomputer ~]# tracepath www.baidu.com
 1?: [LOCALHOST]                      pmtu 1500
 1:  _gateway                                              0.952ms 
 1:  _gateway                                              0.664ms 
 2:  _gateway                                              0.567ms pmtu 1492
 2:  115.32.24.1                                           3.276ms 
 3:  no reply
 4:  no reply

 查看自家路由：
 [root@mingmingxingforcomputer ~]# tracepath 192.168.0.1
 1?: [LOCALHOST]                      pmtu 1500
 1:  _gateway                                              0.666ms reached
 1:  _gateway                                              0.646ms reached
     Resume: pmtu 1500 hops 1 back 1

九、netstat

显示如网络链接、路由表、接口状态等的网络相关信息

[root@mingmingxingforcomputer ~]# netstat -a
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address           Foreign Address         State      
tcp        0      0 mingmingxingforc:domain 0.0.0.0:*               LISTEN     
tcp        0      0 0.0.0.0:ssh             0.0.0.0:*               LISTEN     
tcp        0      0 localhost:ipp           0.0.0.0:*               LISTEN     
tcp        0      0 localhos:x11-ssh-offset 0.0.0.0:*               LISTEN     
tcp        0      0 0.0.0.0:sunrpc          0.0.0.0:*               LISTEN     
tcp        0    208 mingmingxingforcomp:ssh 192.168.0.9:vrtl-vmf-sa ESTABLISHED

[root@mingmingxingforcomputer ~]# netstat -i
Kernel Interface table
Iface             MTU    RX-OK RX-ERR RX-DRP RX-OVR    TX-OK TX-ERR TX-DRP TX-OVR Flg
ens160           1500     6837      0      0 0          2504      0      0      0 BMRU
lo              65536      190      0      0 0           190      0      0      0 LRU
virbr0           1500        0      0      0 0             0      0      0      0 BMU

十、history

显示执行过的命令历史

[root@mingmingxingforcomputer ~]# history | head -n 5
    1  history 
    2  sosreport 
    3  cd /home/
    4  pwd
    5  cd /root

十一、sosreport

收集系统配置及架构信息并输出诊断文档

[root@mingmingxingforcomputer ~]# sosreport 

sosreport (version 3.6)

This command will collect diagnostic and configuration information from
this Red Hat Enterprise Linux system and installed applications.

An archive containing the collected information will be generated in
/var/tmp/sos.r6jscjcn and may be provided to a Red Hat support
representative.

Any information provided to Red Hat will be treated in accordance with
the published support policies at:

  https://access.redhat.com/support/

The generated archive may contain data considered sensitive and its
content should be reviewed by the originating organization before being
passed to any third party.

No changes will be made to system configuration.

Press ENTER to continue, or CTRL-C to quit.

Please enter the case id that you are generating this report for []: y

 Setting up archive ...
 Setting up plugins ...
 Running plugins. Please wait ...

  Finishing plugins              [Running: processor]                                     anager]
  Finished running plugins                                                               
Creating compressed archive...

Your sosreport has been generated and saved in:
  /var/tmp/sosreport-mingmingxingforcomputer-y-2021-06-26-udermtc.tar.xz

The checksum is: 8f5dcd82d59eeb0772bcf32d0688bc78

Please send this file to your support representative.

二、定位文件命令

一、pwd

显示用户当前所处的工做目录

[root@mingmingxingforcomputer ~]# cd ..
[root@mingmingxingforcomputer /]# pwd
/
[root@mingmingxingforcomputer /]# cd /etc
[root@mingmingxingforcomputer etc]# pwd
/etc

二、cd

切换当前的工做路径

[root@mingmingxingforcomputer ~]# cd ..
[root@mingmingxingforcomputer /]# pwd
/

三、ls

显示目录中的文件信息

[root@mingmingxingforcomputer etc]# ls
adjtime                     dracut.conf.d    krb5.conf.d               papersize               sgml
aliases                     egl              ksmtuned.conf             passwd                  shadow
alsa                        enscript.cfg     ld.so.cache               passwd-                 shadow-
alternatives                environment      ld.so.conf                pbm2ppa.conf            shells

参数	做用
-a	看到所有文件
-l	查看文件的属性

四、tree

用于以树状图的形式列出目录内容及结构

[root@mingmingxingforcomputer ~]# tree
.
├── anaconda-ks.cfg
├── a.txt
├── Desktop
├── Documents
├── Downloads
├── initial-setup-ks.cfg
├── linuxprobe
├── Music
├── Pictures
├── Public
├── Templates
└── Videos

五、find

按照指定条件来查找文件所对应的位置

[root@mingmingxingforcomputer ~]# find / -name passwd
/sys/fs/selinux/class/passwd
/sys/fs/selinux/class/passwd/perms/passwd
/etc/pam.d/passwd
/etc/passwd
/var/lib/sss/mc/passwd
/usr/bin/passwd
/usr/share/licenses/passwd
/usr/share/doc/passwd
/usr/share/bash-completion/completions/passwd

进阶实验：在整个文件系统中找出全部归属于linuxprobe用户的文件并复制到/root/findresults目录。

该实验的重点是“-exec {} \;”参数，其中的{}表示find命令搜索出的每个文件，而且命令的结尾必须是“\;”。完成该实验的具体命令以下：

[root@linuxprobe ~]# find / -user linuxprobe -exec cp -a {} /root/findresults/ \;

六、locate

按照名称快速搜索文件所对应的位置

使用步骤：

生成数据库updatedb

locate 文件名称

[root@mingmingxingforcomputer ~]# updatedb 
[root@mingmingxingforcomputer ~]# locate whereis
/usr/bin/whereis
/usr/share/bash-completion/completions/whereis
/usr/share/man/man1/whereis.1.gz
[root@mingmingxingforcomputer ~]# find / -name whereis
/usr/bin/whereis
/usr/share/bash-completion/completions/whereis
[root@mingmingxingforcomputer ~]#

七、whereis

用于按照名称快速搜索二进制程序（命令）、源代码以及帮助手册文件所对应的位置

[root@mingmingxingforcomputer ~]# whereis whereis
whereis: /usr/bin/whereis /usr/share/man/man1/whereis.1.gz

简单来讲，whereis命令也是基于了上述updatedb命令所生成出的索引库文件进行搜索，区别是不关心那些相同名称的文件，仅仅是快速找到对应的命令文件及其帮助文件所在位置。

八、which

which命令用于按照指定名称快速搜索二进制程序（命令）所对应的位置

[root@mingmingxingforcomputer ~]# which whereis
/usr/bin/whereis

查询命令	查询速度	查询准确度
which	1	4
whereis	2	3
locate	3	2
find	4	1

三、文本编辑命令

一、cat

用于查看纯文本文件（内容较少的）

[root@mingmingxingforcomputer ~]# cat -n initial-setup-ks.cfg 
     1  #version=RHEL8
     2  # X Window System configuration information
     3  xconfig  --startxonboot
     4  # License agreement
     5  eula --agreed
     6  # Use graphical install
     7  graphical
     8  # Network information
     9  network  --bootproto=dhcp --device=ens160 --onboot=off --ipv6=auto --no-activate
    10  network  --bootproto=dhcp --hostname=localhost.localdomain
    11  repo --name="AppStream" --baseurl=file:///run/install/repo/AppStream
    12  ignoredisk --only-use=sda

二、more

用于查看纯文本文件（内容较多的）

[root@mingmingxingforcomputer ~]# more -n initial-setup-ks.cfg 
more: unknown option -n
Try 'more --help' for more information.
[root@mingmingxingforcomputer ~]# more initial-setup-ks.cfg 
#version=RHEL8

# X Window System configuration information

xconfig  --startxonboot

# License agreement

eula --agreed

# Use graphical install

graphical

# Network information

network  --bootproto=dhcp --device=ens160 --onboot=off --ipv6=auto --no-activate
network  --bootproto=dhcp --hostname=localhost.localdomain
repo --name="AppStream" --baseurl=file:///run/install/repo/AppStream
ignoredisk --only-use=sda

# Use CDROM installation media

cdrom

# Run the Setup Agent on first boot

firstboot --enable

# System services

services --disabled="chronyd"

# Keyboard layouts

keyboard --vckeymap=us --xlayouts='us'

# System language

lang en_US.UTF-8

--More--(41%)

三、head

用于查看纯文本文件的前N行

[root@mingmingxingforcomputer ~]# head -n 5 initial-setup-ks.cfg 
#version=RHEL8
# X Window System configuration information
xconfig  --startxonboot
# License agreement
eula --agreed

四、tail

用于查看纯文本文件的后N行或持续刷新文件的最新内容

[root@mingmingxingforcomputer ~]# tail -n 5 initial-setup-ks.cfg 
%anaconda
pwpolicy root --minlen=6 --minquality=1 --notstrict --nochanges --notempty
pwpolicy user --minlen=6 --minquality=1 --notstrict --nochanges --emptyok
pwpolicy luks --minlen=6 --minquality=1 --notstrict --nochanges --notempty
%end

tail持续刷新命令：tail -f /var/log/messages

[root@mingmingxingforcomputer ~]# tail -f /var/log/messages
Jun 26 19:55:22 mingmingxingforcomputer systemd[1]: Starting PackageKit Daemon...
Jun 26 19:55:22 mingmingxingforcomputer dbus-daemon[1020]: [system] Successfully activated service 'org.freedesktop.PackageKit'
Jun 26 19:55:22 mingmingxingforcomputer systemd[1]: Started PackageKit Daemon.
Jun 26 20:08:30 mingmingxingforcomputer systemd[1]: Starting dnf makecache...
Jun 26 20:08:30 mingmingxingforcomputer dnf[13946]: Updating Subscription Management repositories.
Jun 26 20:08:30 mingmingxingforcomputer dnf[13946]: Unable to read consumer identity
Jun 26 20:08:30 mingmingxingforcomputer dnf[13946]: This system is not registered to Red Hat Subscription Management. You can use subscription-manager to register.
Jun 26 20:08:30 mingmingxingforcomputer dnf[13946]: Failed determining last makecache time.
Jun 26 20:08:30 mingmingxingforcomputer dnf[13946]: There are no enabled repos.
Jun 26 20:08:30 mingmingxingforcomputer systemd[1]: Started dnf makecache.
……

五、tr

替换文本内容中的字符

语法格式为：“tr [原始字符] [目标字符]”

[root@mingmingxingforcomputer ~]# tail -n 5 initial-setup-ks.cfg | tr [a-z] [A-Z]
%ANACONDA
PWPOLICY ROOT --MINLEN=6 --MINQUALITY=1 --NOTSTRICT --NOCHANGES --NOTEMPTY
PWPOLICY USER --MINLEN=6 --MINQUALITY=1 --NOTSTRICT --NOCHANGES --EMPTYOK
PWPOLICY LUKS --MINLEN=6 --MINQUALITY=1 --NOTSTRICT --NOCHANGES --NOTEMPTY
%END

六、wc

用于统计指定文本文件的行数、字数或字节数

语法格式为：“wc [参数] 文件名称”

[root@mingmingxingforcomputer ~]# wc -clw initial-setup-ks.cfg 
  50  137 1559 initial-setup-ks.cfg

七、stat

用于查看文件的具体存储细节和时间等信息

语法格式为：“stat 文件名称”

[root@mingmingxingforcomputer ~]# stat initial-setup-ks.cfg 
  File: initial-setup-ks.cfg
  Size: 1559        Blocks: 8          IO Block: 4096   regular file
Device: fd00h/64768d    Inode: 35268271    Links: 1
Access: (0644/-rw-r--r--)  Uid: (    0/    root)   Gid: (    0/    root)
Context: system_u:object_r:admin_home_t:s0
Access: 2021-06-26 19:46:18.231530396 +0800
Modify: 2021-01-04 03:40:00.818112167 +0800
Change: 2021-01-04 03:40:00.818112167 +0800
 Birth: -

状态	描述
Access Time	最后一次内容被访问的时间
Modify Time	最后一次内容被修改的时间
Change Time	文件属性最后一次被修改的时间

八、grep

grep命令用于按行提取文本内容

grep [参数] 文件名称

[root@mingmingxingforcomputer ~]# cat initial-setup-ks.cfg | grep oo
xconfig  --startxonboot
network  --bootproto=dhcp --device=ens160 --onboot=off --ipv6=auto --no-activate
network  --bootproto=dhcp --hostname=localhost.localdomain
# Run the Setup Agent on first boot
firstboot --enable
# Root password
rootpw --iscrypted $6$989xgW64eEOskUcc$Oo1jfPK4FIVjw22Fvg5iQxx6mzQ7dw8hqdxjDDbq7LkZYWwB6LGYJfZHZNk6tYnE2HtiGiGhx22L.QK4uqLGe0
# System bootloader configuration
bootloader --location=none
kexec-tools
pwpolicy root --minlen=6 --minquality=1 --notstrict --nochanges --notempty

九、cut

cut命令用于按列提取文本内容

cut [参数] 文件名称

[root@mingmingxingforcomputer ~]# cut -d : -f 1 /etc/passwd
root
bin
daemon
adm
lp
sync
shutdown
halt
mail
operator

十、diff

diff命令用于比较多个文件之间内容的差别

diff [参数] 文件名称A 文件名称B

[root@mingmingxingforcomputer ~]# cat a.txt 
Welcome to linuxprobe.com
Red Hat certified
Free Linux Lessons
Professional guidance
Linux Course
[root@mingmingxingforcomputer ~]# cat b.txt 
Welcome tooo linuxprobe.com

Red Hat certified
Free Linux LeSSonS
////////.....////////
Professional guidance
Linux Course
[root@mingmingxingforcomputer ~]# diff --brief a.txt b.txt 
Files a.txt and b.txt differ
[root@mingmingxingforcomputer ~]# diff -c a.txt b.txt 
*** a.txt   2021-06-26 19:54:36.505573424 +0800
--- b.txt   2021-06-26 19:54:59.510575410 +0800
***************
*** 1,5 ****
! Welcome to linuxprobe.com
  Red Hat certified
! Free Linux Lessons
  Professional guidance
  Linux Course
--- 1,7 ----
! Welcome tooo linuxprobe.com
! 
  Red Hat certified
! Free Linux LeSSonS
! ////////.....////////
  Professional guidance
  Linux Course

十一、uniq

去除查看文件中重复行

uniq [参数] 文件名称

[root@mingmingxingforcomputer ~]# cat c.txt 
aaaaaa
aaaaaa
aaaaaa
1
2
3
4
[root@mingmingxingforcomputer ~]# uniq c.txt 
aaaaaa
1
2
3
4

十二、sort

用于对文本内容进行再排序

sort [参数] 文件名称

[root@mingmingxingforcomputer ~]# sort -n d.txt 
0
12
15
45
78
231
321
[root@mingmingxingforcomputer ~]# cat d.txt 
15
231
12
0
45
78
321

本节课学习命令量很大，须要多练习两遍……不说了，练习去了