During this often happens *nix beginners learn the basic concept without knowing it, you try to ask what the definition of user accounts and Unix to the people that you can consider using Linux / Unix, of course he can not answer it. Sometimes because they do not understand this basic concept, someone who wants to learn Unix to be difficult to grow and always have been when the problem.
Each user’s machine *nix must have an account. User account itself is a collection of characters that explain who the user is, where the user can work, and what can be done.
From my experience, the most important concept that must be related to *nix is:
1. Username or login name or login name
2. Password
3. User Identifier Number (UID)
4. Group Identifier Number (GID)
5. Home Directory
6. Shell-access (I have added because I can access the shell-only bank. Mod security rules)
7. Additional Information
I write all the above can be found in the passwd file in the directory / etc.
USERNAME & UID
Account for each user identified by the username or login unique, there may not be the username or account in the same system.
Unix users use the identification number (UID) to identify an account. Translating between username and UID recorded in the passwd file.
In a small unix system you may not be difficult to provide a username to your users. But for the most unix systems that have hundreds or thousands of users, the username of the user you need a certain tricks that can still follow the principle of making a good username and correct and easy.
Here are some terms of making a good username and correct
1. Login Name must be unique there can not be the same
2. Login Name can not be more than 8 characters, and (it is advisable to use) at least 4 characters.
3. Comprising small letters (not capitalized) of all, though may be forced to use a combination of small and capital letters or all capital letters
4. Login Name in earned easy to remember.
5. Avoid the use of the nickname because the purpose of the login name that is easy to identify anyone who resides in the system.
6. Provide information as possible when possible.
UID will be given the same time when you create a user account. If you want to specify a specific UID to a specific user, the following is the basic rule.
1. UID to a user must be between 100 – 32767 (60000 on the system). UID 0 – 99 special account used to the system by default.
2. UID to a user must be the same if you want to use the multi environment system.
3. Always use a different UID to a different user.
PASSWORD
In addition to the login name, the terms someone can access the system is unix password. Login and password combination is a key to enter and access a system. When the login name is set so easy to remember and easily recognizable to the password requirement is more stringent.
The following tips are a good password and correct.
1. Use a combination of big and small letters (capital), the numbers and unique characters. Password is case sensitive able to detect differences in small and large letters.
2. Easy to remember, so you do not need to show on a piece of paper or on your desk).
3. Typewritten easy so you can quickly typed and can not watched by other people.
4. Cultivated more than 6 characters but less than 10 characters (some unix system that will check the characters more than 10)
5. Do not use words that specializes or popular (such as a sysadmin, administrators, realsysadmin etc.) and in the dictionary. Some cases of password bruteforce obtained by using a list of words that are in the dictionary.
6. Change your password periodically, eg every month.
7. Never give your password to other people because these people may only distribute your password to another person.
Group ID (GID)
To facilitate the distribution of access rights, based on the Unix share user group-specific group. If you want to grouping that some users may have access to a file or folder you can grouping user in the new group.
A user can be incorporated in more than one group, so it can access the files or folders that special can only be accessed by the group.
Group wheel is a special group which the member of this group have special access rights where he can move the user (subtitute users) to become the Super User or root (on the system is not necessary for the wheel group can subtitute users).
Home Directory
Home directory is the first directory that will be found when a user first login. This is the directory in the user’s work and have access to high where he can read, write and write, including the ability to create files, modify files and delete them.
Home users typically been stored in the folder / home and then followed with a user name such as / home / kids. But sometimes easier grouping, can also store a user’s home dir on specific groups such as the folder / home / staff / kids.
Shell-Access
Once a user has a username, password, and homedir, is giving users the right to make the shell-. There are some shell-Medication can be used but that is in common use bash and tcsh. If the user has a shell-access, the user can work in the shell, while if they do not have them (as is usually the sign Not Login), so users will not be allowed to sign.
Users who do not have login access typically used only to run applications such as httpd, nobody, proxy and others. This is used to prevent, when someone successfully take over the application, then the person can not take the username to log into the system further.
Additional Information
Additional information such as full name, address and others can be added into the user account to make it easier to identify a user. Part of this is not a requirement, but if you do not make the most you can quickly find out information about a user.
Approximately such basic user account in Unix and you should know
Tags: Account, information, linux, unix, User