Category Archives: security

Effective User management under Linux/Unix

In this article, we look into the topic of managing our users on our local Linux/Unix box. As we know it, Linux/Unix is a multiuser environment, therefore, one of the main tasks of a system administrator is to create user accounts and provide a secure environment for users to do their work in.

Adding and removing users is still one of the most important task of a system administrator. Therefore, we as system administrators need a good understanding of how the Linux/Unix accounting system works in order to provide good network services to our users and clients.

Good account management is also the key determinant to system security. Infrequently used accounts are prime targets for crackers. So are accounts with weak passwords.

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System integrity using Files, Permissions, Processes, Root and Sudo

To be a good in system administration, we have to understand the basics of files, processes and permissions of our Linux/Unix hosts. Therefore, in this article, we will cover the basic stuffs regarding files, processes, permissions, the SUPERUSER “root” account and the sudo program.

Every file and process on a Linux/Unix system is owned by a particular user account. Every file has both an owner and a group owner. What this means is that the owner of the file enjoys one special property that is not shared with everyone on the system. This property is the ability to modify the permissions of the file.

Other users on the system can’t access files belonging to others without the owner’s permission, so this restriction helps protect a user’s files against “malicious” users!

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