usermod -G groupA 

这样做会使你离开其他用户组,仅仅做为 这个用户组 groupA 的成员。 
应该用 加上 -a 选项: 
usermod -a -G groupA user

(FC4: usermod -G groupA,groupB,groupC user)
-a 代表 append, 也就是 将自己添加到 用户组groupA 中,而不必离开 其他用户组。 

-c, --comment COMMENT         new value of the GECOS field 
-d, --home HOME_DIR           new home directory for the user account 
-e, --expiredate EXPIRE_DATE set account expiration date to EXPIRE_DATE 
-f, --inactive INACTIVE       set password inactive after expiration 
                                to INACTIVE 
-g, --gid GROUP               force use GROUP as new primary group 
-G, --groups GROUPS           new list of supplementary GROUPS 
-a, --append          append the user to the supplemental GROUPS 
                                mentioned by the -G option without removing 
                                him/her from other groups 
-h, --help                    display this help message and exit 
-l, --login NEW_LOGIN         new value of the login name 
-L, --lock                    lock the user account 
-m, --move-home               move contents of the home directory to the new 
                                location (use only with -d) 
-o, --non-unique              allow using duplicate (non-unique) UID 
-p, --password PASSWORD       use encrypted password for the new password 
-s, --shell SHELL             new login shell for the user account 
-u, --uid UID                 new UID for the user account 
-U, --unlock                  unlock the user account


查看用户所属的组使用命令:$ groups user

或者查看文件:$ cat /etc/group

posted @ 2015-11-26 00:01  小浩学长  阅读(199)  评论(0编辑  收藏