给Linux添加新用户，新建用户，新建帐号
添加用户组
sudo groupadd groupname添加用户
sudo useradd username -m -s /bin/bash -d /home/username -g groupname
-s /sbin/nologin 设置不能登陆 -s /bin/false(老方法) 也行
-d 设置用户主目录
-g 用户组
-m 创建用户目录useradd的具体参数为
[root@317304 ~]# useradd --help
Usage: useradd [options] LOGIN
Options:
-b, --base-dir BASE_DIR base directory for the home directory of the
new account
-c, --comment COMMENT GECOS field of the new account
-d, --home-dir HOME_DIR home directory of the new account
-D, --defaults print or change default useradd configuration
-e, --expiredate EXPIRE_DATE expiration date of the new account
-f, --inactive INACTIVE password inactivity period of the new account
-g, --gid GROUP name or ID of the primary group of the new
account
-G, --groups GROUPS list of supplementary groups of the new
account
-h, --help display this help message and exit
-k, --skel SKEL_DIR use this alternative skeleton directory
-K, --key KEY=VALUE override /etc/login.defs defaults
-l, --no-log-init do not add the user to the lastlog and
faillog databases
-m, --create-home create the user's home directory
-M, --no-create-home do not create the user's home directory
-N, --no-user-group do not create a group with the same name as
the user
-o, --non-unique allow to create users with duplicate
(non-unique) UID
-p, --password PASSWORD encrypted password of the new account
-r, --system create a system account
-s, --shell SHELL login shell of the new account
-u, --uid UID user ID of the new account
-U, --user-group create a group with the same name as the user
-Z, --selinux-user SEUSER use a specific SEUSER for the SELinux user mapping更改用户登录权限
在增加了-s /sbin/nologin 参数后，那么这个帐号就不能登陆了，如果想要恢复登陆使用
sudo usermod -s /bin/bash username禁用用户登录权限
sudo usermod -s /sbin/nologin username设置密码
给用户设置密码，这样帐号就能使用了。
sudo passwd username删除用户
删除用户
sudo userdel username