LinuxTips(RedHat系)

ユーザーの設定を変更するユーザーには予め、UIDやGID、ホームディレクトリなどが指定されている。これらの情報を後から変...

ユーザーを削除するユーザーを削除するコマンドはuserdel。このコマンドを実行すると、ユーザー情報は削除されるが、ユー...

一般ユーザーでroot権限のコマンドを実行する一般ユーザーでログインの時、root権限のコマンドを使用する場合は、sud...

他のユーザにファイルを見せないようにするLinuxでは、他のユーザにファイルを見せないようにすることができる。chmod...

To create and add a new user, use the "useradd" commandBy specifying a user name as an argument to the command, a user will be created. The user directory will be created under the /home directory, and the group name will be the same as the user name.

To create and add a new group, use the "groupadd" command.Information about groups is described in /etc/group and can be edited, but it is better to edit the group information with the vigr command instead of directly editing the "/etc/group" file.

Check the group in /etc/passwd and /etc/group (check the gid)Users always belong to a group, and the group described in the /etc/passwd and /etc/group files is the primary group.The gid (group ID) is stored in the /etc/passwd and /etc/group files

Group information in Linux is stored in the "/etc/group" file, which has the following notationtama:x:500:From left to right, tama is the group name, X is the password (when it says X, it is written in the /etc/gshadow file). 500 is the GID.To make a user belong to multiple groups, edit the "/etc/group" file, but it is convenient to use the vigr command to edit the "/etc/group" file. (The operation method is the same as vi)

The user's login history will be output to the /var/run/utmp and /var/log/wtmp files.This file, like the /var/log/lastlog and /var/log/btmp files, is a binary file, so it cannot be displayed by the less, cat, or tail commands.To display it, use the dedicated /usr/bin/last command.