Database
Mysql Tutorial
Detailed explanation of Linux system user management and grep regular expressions
Detailed explanation of Linux system user management and grep regular expressions
本文主要给大家介绍了关于linux系统用户管理与grep正则表达式的相关资料，文中通过示例代码介绍的非常详细，对大家学习或者使用linux系统具有一定的参考学习价值，希望能帮助到大家。
linux系统用户管理与grep正则表达式
1、复制/etc/skel目录为/home/tuser1，要求/home/tuser1及其内部文件的属组和其它用户均没有任何访问权限。
[root@suywien ~]# cp -rpv /etc/skel/ /home/tuser1/ ‘/etc/skel/' -> ‘/home/tuser1/' ‘/etc/skel/.mozilla' -> ‘/home/tuser1/.mozilla' ‘/etc/skel/.mozilla/extensions' -> ‘/home/tuser1/.mozilla/extensions' ‘/etc/skel/.mozilla/plugins' -> ‘/home/tuser1/.mozilla/plugins' ‘/etc/skel/.bash_logout' -> ‘/home/tuser1/.bash_logout' ‘/etc/skel/.bash_profile' -> ‘/home/tuser1/.bash_profile' ‘/etc/skel/.bashrc' -> ‘/home/tuser1/.bashrc' [root@suywien ~]# useradd tuser -d /home/tuser1/ useradd: warning: the home directory already exists. Not copying any file from skel directory into it. [root@suywien ~]# chmod -R go-rwx /home/tuser1/ [root@suywien ~]# ll -d /home/tuser1/ drwx------ 3 root root 74 Feb 12 03:04 /home/tuser1/
2、编辑/etc/group文件，添加组hadoop。
[root@suywien ~]# vim /etc/group [root@suywien ~]# tail -1 /etc/group hadoop:x:1029
3、手动编辑/etc/passwd文件新增一行，添加用户hadoop，其基本组ID为hadoop组的id号；其家目录为/home/hadoop。
[root@suywien ~]# vim /etc/passwd [root@suywien ~]# tail -1 /etc/passwd hadoop:x:1029:1029::/home/hodoop/:/bin/bash
4、复制/etc/skel目录为/home/hadoop，要求修改hadoop目录的属组和其它用户没有任何访问权限。
[root@suywien ~]# cp -fpv /etc/skel/ /home/hadoop cp: omitting directory ‘/etc/skel/' [root@suywien ~]# cp -fpvR /etc/skel/ /home/hadoop ‘/etc/skel/' -> ‘/home/hadoop' ‘/etc/skel/.mozilla' -> ‘/home/hadoop/.mozilla' ‘/etc/skel/.mozilla/extensions' -> ‘/home/hadoop/.mozilla/extensions' ‘/etc/skel/.mozilla/plugins' -> ‘/home/hadoop/.mozilla/plugins' ‘/etc/skel/.bash_logout' -> ‘/home/hadoop/.bash_logout' ‘/etc/skel/.bash_profile' -> ‘/home/hadoop/.bash_profile' ‘/etc/skel/.bashrc' -> ‘/home/hadoop/.bashrc' [root@suywien ~]# chmod go-rwx /home/hadoop/ [root@suywien ~]# ls -ld /home/hadoop/ drwx------ 3 root root 74 Feb 12 03:04 /home/hadoop/
5、修改/home/hadoop目录及其内部所有文件的属主为hadoop，属组为hadoop。
[root@suywien ~]# chown -R hadoop:hadoop /home/hadoop/ [root@suywien ~]# ll -al /home/hadoop/ total 16 drwx------ 3 hadoop hadoop 74 Feb 12 03:04 . drwxr-xr-x. 10 root root 4096 Mar 25 10:14 .. -rw-r--r-- 1 hadoop hadoop 18 Nov 20 2015 .bash_logout -rw-r--r-- 1 hadoop hadoop 193 Nov 20 2015 .bash_profile -rw-r--r-- 1 hadoop hadoop 231 Nov 20 2015 .bashrc drwxr-xr-x 4 hadoop hadoop 37 Feb 12 03:03 .mozilla
6、显示/proc/meminfo文件中以大写或小写S开头的行；用两种方式；
[root@suywien ~]# grep ^[S,s] /proc/meminfo SwapCached: 0 kB SwapTotal: 2097148 kB SwapFree: 2097148 kB Shmem: 9100 kB Slab: 89476 kB SReclaimable: 53176 kB SUnreclaim: 36300 kB
[root@suywien ~]# grep -i "^s" /proc/meminfo SwapCached: 0 kB SwapTotal: 2097148 kB SwapFree: 2097148 kB Shmem: 9100 kB
7、显示/etc/passwd文件中其默认shell为非/sbin/nologin的用户；
[root@suywien ~]# grep \/sbin\/nologin$ /etc/passwd bin:x:1:1:bin:/bin:/sbin/nologin daemon:x:2:2:daemon:/sbin:/sbin/nologin adm:x:3:4:adm:/var/adm:/sbin/nologin lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin mail:x:8:12:mail:/var/spool/mail:/sbin/nologin ......
8、显示/etc/passwd文件中其默认shell为/bin/bash的用户；
[root@suywien ~]# grep \/bin\/bash /etc/passwd root:x:0:0:root:/root:/bin/bash roo:x:1000:1000:root:/home/roo:/bin/bash gentoo:x:4001:4001::/home/gentoo:/bin/bash mageia:x:1100:1100::/home/linux:/bin/bash tuser:x:4003:4003::/home/tuser1/:/bin/bash hadoop:x:1029:1029::/home/hodoop/:/bin/bash
9、找出/etc/passwd文件中的一位数或两位数；
[root@suywien ~]# grep "\<[0-9]\{2,3\}\>" /etc/passwd
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
operator:x:11:0:operator:/root:/sbin/nologin
games:x:12:100:games:/usr/games:/sbin/nologin
ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
......10、显示/boot/grub/grub.conf中以至少一个空白字符开头的行；
[root@suywien ~]# grep "^[[:space:]]\+" /boot/grub2/grub.cfg
load_env
set default="${next_entry}"
set next_entry=
save_env next_entry
set boot_once=true
......11、显示/etc/rc.d/rc.sysinit文件中以#开头，后面跟至少一个空白字符，而后又有至少一个非空白字符的行；
[root@suywien ~]# grep "^#[[:space:]]\+[^[:space:]]\+" /etc/rc.d/rc.local # THIS FILE IS ADDED FOR COMPATIBILITY PURPOSES # It is highly advisable to create own systemd services or udev rules # to run scripts during boot instead of using this file. # In contrast to previous versions due to parallel execution during boot # this script will NOT be run after all other services. # Please note that you must run 'chmod +x /etc/rc.d/rc.local' to ensure # that this script will be executed during boot.
12、打出netstat -tan命令执行结果中以‘LISTEN'，后或跟空白字符结尾的行；
[root@suywien ~]# netstat -tan | grep "LISTEN[[:space:]]*$" tcp 0 0 192.168.122.1:53 0.0.0.0:* LISTEN tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN tcp6 0 0 :::22 :::* LISTEN tcp6 0 0 ::1:631 :::* LISTEN tcp6 0 0 ::1:25 :::* LISTEN
13、添加用户bash, testbash, basher, nologin (此一个用户的shell为/sbin/nologin)，而后找出当前系统上其用户名和默认shell相同的用户的信息；
[root@suywien ~]# useradd bash [root@suywien ~]# useradd basher [root@suywien ~]# useradd -s /sbin/nologin nologin [root@suywien ~]# grep -E "^([^:]+\>).*\1$" /etc/passwd sync:x:5:0:sync:/sbin:/bin/sync shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown halt:x:7:0:halt:/sbin:/sbin/halt bash:x:4004:4004::/home/bash:/bin/bash nologin:x:4006:4006::/home/nologin:/sbin/nologin
相关推荐：
The above is the detailed content of Detailed explanation of Linux system user management and grep regular expressions. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
1664
14
1422
52
1316
25
1267
29
1239
24
Linux Architecture: Unveiling the 5 Basic Components
Apr 20, 2025 am 12:04 AM
The five basic components of the Linux system are: 1. Kernel, 2. System library, 3. System utilities, 4. Graphical user interface, 5. Applications. The kernel manages hardware resources, the system library provides precompiled functions, system utilities are used for system management, the GUI provides visual interaction, and applications use these components to implement functions.
How to check the warehouse address of git
Apr 17, 2025 pm 01:54 PM
To view the Git repository address, perform the following steps: 1. Open the command line and navigate to the repository directory; 2. Run the "git remote -v" command; 3. View the repository name in the output and its corresponding address.
vscode Previous Next Shortcut Key
Apr 15, 2025 pm 10:51 PM
VS Code One-step/Next step shortcut key usage: One-step (backward): Windows/Linux: Ctrl ←; macOS: Cmd ←Next step (forward): Windows/Linux: Ctrl →; macOS: Cmd →
How to run java code in notepad
Apr 16, 2025 pm 07:39 PM
Although Notepad cannot run Java code directly, it can be achieved by using other tools: using the command line compiler (javac) to generate a bytecode file (filename.class). Use the Java interpreter (java) to interpret bytecode, execute the code, and output the result.
What is the main purpose of Linux?
Apr 16, 2025 am 12:19 AM
The main uses of Linux include: 1. Server operating system, 2. Embedded system, 3. Desktop operating system, 4. Development and testing environment. Linux excels in these areas, providing stability, security and efficient development tools.
How to run sublime after writing the code
Apr 16, 2025 am 08:51 AM
There are six ways to run code in Sublime: through hotkeys, menus, build systems, command lines, set default build systems, and custom build commands, and run individual files/projects by right-clicking on projects/files. The build system availability depends on the installation of Sublime Text.
laravel installation code
Apr 18, 2025 pm 12:30 PM
To install Laravel, follow these steps in sequence: Install Composer (for macOS/Linux and Windows) Install Laravel Installer Create a new project Start Service Access Application (URL: http://127.0.0.1:8000) Set up the database connection (if required)
git software installation
Apr 17, 2025 am 11:57 AM
Installing Git software includes the following steps: Download the installation package and run the installation package to verify the installation configuration Git installation Git Bash (Windows only)
