Linux中一些常见的命令(中)
history
[root@hadoop001 ~]# history
1 vi /etc/sysconfig/network
2 hostname
3 hostname hadoop001
......
[root@hadoop001 ~]# !48 # 执行第48个命令
source /etc/profile
清空历史命令
echo "" > ~/.bash_history
[root@hadoop001 ~]# echo "" > .bash_history
[root@hadoop001 ~]# history
1 123
2 alias 123='cd /root/bigdata/'
3 alias he='cat /root/bigdata/hello.txt20190311'
......
#注意：需要重新打开一个会话才生效
[root@hadoop001 ~]# history
1 history
[root@hadoop001 ~]# cat .bash_history
[root@hadoop001 ~]#
用户的常用命令
[root@hadoop001 ~]# ll /usr/sbin/user*
-rwxr-x---. 1 root root 103096 Dec 8 2011 /usr/sbin/useradd
-rwxr-x---. 1 root root 69560 Dec 8 2011 /usr/sbin/userdel
-rws--x--x. 1 root root 42384 Aug 23 2010 /usr/sbin/userhelper
-rwxr-x---. 1 root root 98680 Dec 8 2011 /usr/sbin/usermod
-rwsr-xr-x. 1 root root 9000 Nov 23 2013 /usr/sbin/usernetctl
#用户组的常用命令
[root@hadoop001 ~]# ll /usr/sbin/group*
-rwxr-x---. 1 root root 54968 Dec 8 2011 /usr/sbin/groupadd
-rwxr-x---. 1 root root 46512 Dec 8 2011 /usr/sbin/groupdel
-rwxr-x---. 1 root root 50800 Dec 8 2011 /usr/sbin/groupmems
-rwxr-x---. 1 root root 61360 Dec 8 2011 /usr/sbin/groupmod
[root@hadoop001 ~]#
#注意：一个人可以有多个用户组，但是必须只有一个主组
[root@hadoop001 home]# useradd haha
[root@hadoop001 home]# ll
total 8
drwx------. 4 haha haha 4096 Mar 12 22:09 haha
drwx------. 4 justdodt justdodt 4096 Mar 12 19:02 justdodt
[root@hadoop001 home]# id justdodt
uid=500(justdodt) gid=500(justdodt) groups=500(justdodt)
[root@hadoop001 home]# id haha
uid=501(haha) gid=501(haha) groups=501(haha)
#gid 是主组，groups 是所有组
[root@hadoop001 home]# cat /etc/passwd
root:x:0:0:root:/root:/bin/bash
.
.
.
justdodt:x:500:500:justdodt:/home/justdodt:/bin/bash
haha:x:501:501::/home/haha:/bin/bash
[root@hadoop001 home]#
[root@hadoop001 home]# cat /etc/group
root:x:0:
bin:x:1:bin,daemon
.
.
.
justdodt:x:500:
haha:x:501:
[root@hadoop001 home]#
删除用户
[root@hadoop001 ~]# userdel haha
[root@hadoop001 ~]# cat /etc/passwd
root:x:0:0:root:/root:/bin/bash
.
.
.
tcpdump:x:72:72::/:/sbin/nologin
justdodt:x:500:500:justdodt:/home/justdodt:/bin/bash
[root@hadoop001 ~]# cat /etc/group
root:x:0:
bin:x:1:bin,daemon
.
.
.
slocate:x:21:
justdodt:x:500:
[root@hadoop001 ~]#
[root@hadoop001 ~]# ll /home/
total 8
drwx------. 4 501 501 4096 Mar 12 22:09 haha
drwx------. 4 justdodt justdodt 4096 Mar 12 19:02 justdodt
[root@hadoop001 ~]#
#注意：**删除用户后，/etc/passwd和/etc/group都没有记录，因为haha该组只有一个用户haha，用户被删除，组校验就他自己，就删除；但是家目录还在。
重新创建用户
[root@hadoop001 ~]# useradd haha
useradd: warning: the home directory already exists.
Not copying any file from skel directory into it.
Creating mailbox file: File exists
[root@hadoop001 ~]# id haha
uid=501(haha) gid=501(haha) groups=501(haha)
[root@hadoop001 ~]# groupadd bigdata
[root@hadoop001 ~]# id haha
uid=501(haha) gid=501(haha) groups=501(haha)
[root@hadoop001 ~]# usermod -a -G bigdata haha
[root@hadoop001 ~]# id haha
uid=501(haha) gid=501(haha) groups=501(haha),502(bigdata)
[root@hadoop001 ~]# usermod -g bigdata haha
[root@hadoop001 ~]# id haha
uid=501(haha) gid=502(bigdata) groups=502(bigdata)
[root@hadoop001 ~]# usermod -a -G haha haha
[root@hadoop001 ~]# id haha
uid=501(haha) gid=502(bigdata) groups=502(bigdata),501(haha)
[root@hadoop001 ~]#
设置密码
[root@hadoop001 ~]# passwd haha
Changing password for user haha.
New password:
BAD PASSWORD: it is too simplistic/systematic
BAD PASSWORD: is too simple
Retype new password:
Retype new password:
passwd: all authentication tokens updated successfully.
[root@hadoop001 ~]#
[root@hadoop001 ~]#
切换用户
[root@hadoop001 ~]# su - haha
[haha@hadoop001 ~] pwd
/home/haha
[haha@hadoop001 ~]
[haha@hadoop001 ~] su - justdodt
Password:
[justdodt@hadoop001 ~] pwd
/home/justdodt
[haha@hadoop001 ~] su haha
Password:
[haha@hadoop001 ~] su justdodt
Password:
[justdodt@hadoop001 haha]$ pwd
/home/haha
#注意： - 代表切换用户后，进入到该用户的家目录且执行环境变量文件。
[haha@hadoop001 ~]$ alias
alias l.='ls -d .* --color=auto'
alias ll='ls -l --color=auto'
alias ls='ls --color=auto'
alias vi='vim'
alias which='alias | /usr/bin/which --tty-only --read-alias --show-dot --show-tilde'
[haha@hadoop001 ~]$ su - haha
Password:
[haha@hadoop001 ~]$ pwd
/home/haha
[haha@hadoop001 ~]$ alias
alias 123='cd /root/bigdata/'
alias he='cat /root/bigdata/hello.txt20190311'
alias l.='ls -d .* --color=auto'
alias ll='ls -l --color=auto'
alias ls='ls --color=auto'
alias vi='vim'
alias which='alias | /usr/bin/which --tty-only --read-alias --show-dot --show-tilde'
[haha@hadoop001 ~]$
临时获取root最大权限
[haha@hadoop001 ~]$ ll /root/
ls: cannot open directory /root/: Permission denied
[root@hadoop001 ~]# vi /etc/sudoers
## Sudoers allows particular users to run various commands as
## the root user, without needing the root password.
.
.
.
## Allow root to run any commands anywhere
root ALL=(ALL) ALL
haha ALL=(root) NOPASSWD:ALL
[root@hadoop001 ~]# su - haha
[haha@hadoop001 ~]$ ll /root/
ls: cannot open directory /root/: Permission denied
[haha@hadoop001 ~]$ sudo ll /root/
sudo: ll: command not found
[haha@hadoop001 ~]$ sudo ls -l /root/
total 108
-rw-------. 1 root root 1383 Mar 12 20:01 anaconda-ks.cfg
drwxr-xr-x. 3 root root 4096 Mar 12 17:46 bigdata
drwxr-xr-x. 2 root root 4096 Mar 12 12:23 Desktop
drwxr-xr-x. 2 root root 4096 Mar 12 12:23 Documents
drwxr-xr-x. 2 root root 4096 Mar 12 12:23 Downloads
-rw-r--r--. 1 root root 49565 Mar 12 20:01 install.log
-rw-r--r--. 1 root root 10033 Mar 12 19:59 install.log.syslog
drwxr-xr-x. 2 root root 4096 Mar 12 12:23 Music
drwxr-xr-x. 2 root root 4096 Mar 12 12:23 Pictures
drwxr-xr-x. 2 root root 4096 Mar 12 12:23 Public
drwxr-xr-x. 2 root root 4096 Mar 12 12:23 Templates
drwxr-xr-x. 2 root root 4096 Mar 12 12:23 Videos
[haha@hadoop001 ~]$
管道符，过滤 | grep
[root@hadoop001 ~]# cat /etc/passwd | grep haha
haha:x:501:502::/home/haha:/bin/bash
[root@hadoop001 ~]# cat /etc/passwd | grep haha
haha:x:501:502::/home/haha:/bin/bash
[root@hadoop001 ~]# ps -ef | grep tail
root 31334 30804 0 00:54 pts/7 00:00:00 tail -f /root/bigdata/hello.txt20190311
root 31337 31298 0 00:54 pts/2 00:00:00 grep tail
[root@hadoop001 ~]# ps -ef | grep tail | grep -v grep`
root 31334 30804 0 00:54 pts/7 00:00:00 tail -f /root/bigdata/hello.txt20190311
进程号
[root@hadoop001 ~]# ps -ef | grep tail
root 31334 30804 0 00:54 pts/7 00:00:00 tail -f /root/bigdata/hello.txt20190311
root 31337 31298 0 00:54 pts/2 00:00:00 grep tail
端口号，不是所有的进程号都有端口号
[root@hadoop001 ~]# netstat -nlp | grep 31334
[root@hadoop001 ~]# ps -ef | grep ssh
root 1455 1 0 Mar12 ? 00:00:00 /usr/sbin/sshd
root 30577 1455 0 Mar12 ? 00:00:00 sshd: root@pts/2
root 30604 1455 0 Mar12 ? 00:00:00 sshd: root@pts/3
root 30627 1455 0 Mar12 ? 00:00:00 sshd: root@pts/4
root 30800 1455 0 Mar12 ? 00:00:00 sshd: root@pts/7
root 31381 31298 0 01:02 pts/2 00:00:00 grep ssh
[root@hadoop001 ~]#
[root@hadoop001 ~]# netstat -nlp | grep 1455
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1455/sshd
tcp 0 0 :::22 :::* LISTEN 1455/sshd
杀死进程，kill -9
[root@hadoop001 ~]# ps -ef | grep tail
root 31334 30804 0 00:54 pts/7 00:00:00 tail -f /root/bigdata/hello.txt20190311
root 31396 31298 0 01:04 pts/2 00:00:00 grep tail
[root@hadoop001 ~]#
[root@hadoop001 ~]#
[root@hadoop001 ~]# kill -9 $(pgrep -f txt)
[root@hadoop001 ~]# ps -ef | grep tail`
root 31399 31298 0 01:04 pts/2 00:00:00 grep tail
[root@hadoop001 ~]#
#注意：kill -9 $(pgrep -f txt) 杀死带txt字符的所有进程
搜索 history ，find
[root@hadoop001 ~]# history | grep ps
27 ps -ef | grep tail
28 ps -ef | grep tail | grep -v grep
29 ps -ef | grep 'log'
30 ps -ef | grep tail | grep -v grep
32 ps -ef | grep ssh
35 ps -ef | grep tail
37 ps -ef | grep tail
39 ps -ef | grep tail
40 history | grep ps
[root@hadoop001 ~]# find / -name 'bigdata'
/root/bigdata
模糊匹配
[root@hadoop001 ~]# find / -name 'bigd*'
/root/bigdata
安装rpm 软件包
[root@hadoop001 ~]# yum search http # 首先搜索
[root@hadoop001 ~]# yum install -y httpd
卸载rpm 软件包 rpm -e , rpm -e –nodeps 不检查依赖卸载
[root@hadoop001 ~]# rpm -qa|grep httpd #首先查看安装的软件包
httpd-2.2.15-69.el6.centos.x86_64
httpd-tools-2.2.15-69.el6.centos.x86_64
[root@hadoop001 ~]# rpm -e httpd-2.2.15-69.el6.centos.x86_64
error: Failed dependencies:
httpd >= 2.2.0 is needed by (installed) gnome-user-share-2.28.2-3.el6.x86_64
[root@hadoop001 ~]# rpm -e --nodeps httpd-2.2.15-69.el6.centos.x86_64
warning: /etc/httpd/conf/httpd.conf saved as /etc/httpd/conf/httpd.conf.rpmsave
which ,去$PATH中找
[root@hadoop001 ~]# echo $PATH
/usr/lib64/qt-3.3/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin
[root@hadoop001 ~]# which is
/usr/bin/which: no is in (/usr/lib64/qt-3.3/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin)
--help 和 man 命令都是查看命令帮助，但是man更加详细。（man命令的戏称，有事找男人）
