Linux: Log Everyone Out Of The System

I can login as root user on Debian or Ubuntu/RHEL/CentOS Linux based system. I need to log everyone off (all ssh users) to install new kernel and/or hardware. How do I do this on Linux?…

Linux / Unix: Check Last Time User Logged In On The System

I am a new Unix system admin. How do I find ouw who has recently use the Linux or Unix-like server? Which terminals they used, and when they logged in and out of the my…

Linux: Hide Processes From Other Users

I run a multi-user system. Most users access resources using ssh client. How can I stop leaking process information to all users on Linux operating systems? How do I prevent users from seeing processes that…

How To Add, Delete, and Grant Sudo Privileges to Users on a FreeBSD Server

I ‘m setting up a new FreeBSD server. I do not want to use a default root user who has full system access. How can I setup and grant sudo privileges to users on a…

FreeBSD Add a User To Wheel Group Command

H ow do I add a user to the wheel group in FreeBSD unix operating systems using command line options?   You need to use the pw command line utility for adding, modifying and removing…

How to force users to use secure passwords on Ubuntu/Debian Linux

M y Linux shell user can modify their password using the passwd command. How can I force users to choose the secure password that will prevent users from using stupid passwords like “abc123”, “password”, “123456”…

How to create a new sudo user on Ubuntu Linux server

I am a new Ubuntu Linux 16.04.xx LTS server user. How do I create a new sudo user on my server? How do I add a new user as sudoer file using the command line…

userdel: user vivek is currently used by process 749 error and fix on Linux

I am trying to delete a user named vivek using the userdel command as follows userdel -r vivek userdel: user vivek is currently used by process 749 How do I fix this problem and delete…