day03-01 Amin linux-user and Group management

day03-01 Amin linux-user and Group management

3.1 User profile and password configuration files

/etc/passwd  用户信息配置文件/etc/shadow  用户密码配置文件        [[email protected] tmp]# cat /etc/passwd        root:x:0:0:root:/root:/bin/bash        bin:x:1:1:bin:/bin:/sbin/nologin        .............................        user1:x:1000:1000::/home/user1:/bin/bash        aming:x:1001:1001::/home/aming:/bin/bashusername： ：uid:gid:注释:家目录：shell        [[email protected] tmp]# cat /etc/shadow        root:$6$Nat9OJRo$0qg5VdrCwNmGzXu8BXpu/mHfyRIE52/Vq1BuaOfiAYuA/14tPVv9S2QRYWUxWx0F9DXsIXM        9ESeZ42NoEJgJ40:17586:0:99999:7:::bin:*:17110:0:99999:7:::        ............................        user1:!!:17587:0:99999:7:::        aming:!!:17587:0:99999:7:::username:加密的密码：最近更改密码的日期1970-更改密码的时间：多少天之后才可以更改密码：密码多少天后到期，多少天之内更改密码：密码到期前的警告天数：账号失效期限：账号在此日期前可以使用：保留字段

3.2 User Group Management

/etc/group    组信息配置文件/etc/gshadow  组密码配置文件groupadd  grp1        [[email protected] tmp]# groupadd  grp1        [[email protected] tmp]# groupadd -g 1005 grp2groupdel grp1        [[email protected] tmp]# groupdel grp2        [[email protected] tmp]# tail -n2 /etc/group        slocate:x:21:        grp1:x:1002:        [[email protected] tmp]# groupdel usr1        groupdel：“usr1”组不存在        [[email protected] tmp]# groupdel user1        groupdel：不能移除用户“user1”的主组删除用户组，不可以删除有用户存在的组

3.3 User Management

Useradd-u Specify uid-g Specify gid-d Specify home directory name-s specify shell-m do not create home directory [[email protected] tmp]# Useradd User2 [[email protected] tmp]# tail-n2/etc/passwd aming:x:1001:1001::/home/aming:/bin/bash US Er2:x:1002:1003::/home/user2:/bin/bash [[email protected] tmp]# useradd-u 1004-g grp1 user3 [[EMAIL&N Bsp;protected] tmp]# tail-n3/etc/passwd aming:x:1001:1001::/home/aming:/bin/bash user2:x:1002:1003::/home/ User2:/bin/bash User3:x:1004:1002::/home/user3:/bin/bash [[email protected] tmp]# useradd-u 1006-g gr p1-d/home/aming111-s/sbin/nologin user4 [[email protected] tmp]# tail-n3/etc/passwd user2:x:1002: 1003::/home/user2:/bin/bash User3:x:1004:1002::/home/user3:/bin/bash User4:x:1006:1002::/home/aming111:/sbin        /nologin [[email protected] tmp]# useradd-m user5 [[email protected] tmp]# tail-n3/etc/passwd USER3:X:1004:1002::/home/user3:/bin/bash user4:x:1006:1002::/home/aming111:/sbin/nologin user5:x:1007:1007::/home/user5:/bin/b Ash [[email protected] tmp]# ls/home/aming aming111 user1 user2 user3userdel Delete user does not delete user home directory- R Delete User Delete home directory at the same time [[email protected] tmp]# userdel user8 [[email protected] tmp]# ls/home/am ing aming111 user1 user2 user3 User8

3.4 Usermod Changing user properties

usermod     -u 1006 username    -g 1009 username    -d /home/name    -s /sbin/nologin    -G user1,grp1,aming    -g user1

3.5 User Password Management

passwd    -l username  锁定用户密码    -u username  解锁用户密码usermod -L username  锁定用户密码usermod -U username  解锁用户密码        echo "123456"|passwd --stdin username  更改用户密码        [[email protected] tmp]# echo -e "123\nsss"        123        sss        [[email protected] tmp]# echo -e "123\tsss"        123 sss

3.6 mkpasswd

Make passwd
Yum Install-y expect

    [[email protected] tmp]# mkpasswd    xOW9ga[f7    [[email protected] tmp]# mkpasswd -l 12    gzcM37qhxuV|    [[email protected] tmp]# mkpasswd -l 12 -s 3    kmK).4o~zu2F    [[email protected] tmp]# mkpasswd -l 12 -s 0    ojmt8UhyB3do

3.7 su Command

su -  加载完整的环境变量和配置文件su - -c "touch /tmp/aming.111" aming  以aming运行命令        [[email protected] tmp]# ls -la /etc/skel/        总用量 24        drwxr-xr-x.  2 root root   62 2月  24 22:18 .        drwxr-xr-x. 74 root root 8192 2月  26 00:14 ..        -rw-r--r--.  1 root root   18 8月   3 2017 .bash_logout        -rw-r--r--.  1 root root  193 8月   3 2017 .bash_profile        -rw-r--r--.  1 root root  231 8月   3 2017 .bashrc

3.8 sudo command

Authorizing a normal user to execute a command [[email protected] tmp]# Visudo # allow ROOT to run any commands anywhere root AL L= (All) all aming all= (All)/usr/bin/ls,/usr/bin/mv,/usr/bin/cat amings all= (All) Nopas SWD:/usr/bin/su # # Host Aliases # Groups of machines.        Prefer to use Hostnames (perhaps using # wildcards for entire domains) or IP addresses instead.  # Host_alias fileservers = FS1, FS2 # Host_alias mailservers = SMTP, SMTP2 # User Aliases # # These aren ' t often necessary, as can use regular groups # # (ie, from files, LDAP, NIS, etc) in this File-jus t use%groupname # # rather than Useralias # User_alias ADMINS = jsmith, mikem amings_alias ADMINS = u Ser1,user2 # # Command Aliases # These is groups of related commands ... # # # Networking # Cmnd_ Alias NETWORKING =/sbin/route,/sbin/ifconfig,/bin/ping,/sbin/dhclient,/usr/b in/net,/sbin/iptables,/usr/bin/rfcomm,/usr/bin/wvdial,/sbin/iwconfig,/sbin/mii-tool # # Installation        and management of software # Cmnd_alias software =/bin/rpm,/usr/bin/up2date,/usr/bin/yum # Services # Cmnd_alias SERVICES =/sbin/service,/sbin/chkconfig,/usr/bin/systemctl start,/usr/b in/systemctl stop,/usr /bin/systemctl Reload,/usr/bin/systemctl restart,/usr/bin/systemctl status,/usr/bin/systemctl Enable,/usr/bin/ Systemctl Disable # Updating The Locate database # Cmnd_alias locate =/usr/bin/updatedb [[Email&nbs P;protected] ~]$ sudo/usr/bin/ls/root/[[email protected] ~]$ sudo/usr/bin/cat/root/

3.9 Restricting root Telnet

Local login cannot be restricted

    [[email protected] tmp]# vi /etc/ssh/sshd_config    #LoginGraceTime 2m    PermitRootLogin no

day03-01 Amin linux-user and Group management