How to disable root ssh login in Linux

Muhammad Ali Ahmed — Mon, 26 Aug 2024 11:19:51 +0000

Before Getting Started

It is important to understand why it is important to disable root ssh login in Linux

Disabling direct SSH root login is a crucial security measure that helps protect your servers from unauthorized access and potential breaches. Root accounts have unrestricted access to the entire system, so if an attacker gains access to the root account, they can potentially control everything on the server. By disabling root SSH login, you enforce the use of lower-privileged accounts for remote access. Users must log in with their accounts and escalate privileges using sudo if necessary. This minimizes the risk and improves accountability, as each action can be traced back to a specific user rather than the all-powerful root.

You have to edit the sshd_config file

Navigate to the /etc/ssh directory

cd /etc/ssh
Open the sshd_config file in a text editor

nano sshd_config

or

vim sshd_config
Edit the file

Look for the line "PermitRootLogin"
It may be commented out and its value can be yes, no, or
prohibit-password. you have to uncomment it and write
```
 PermitRootLogin no
```
Restart the ssh service

sudo systemctl restart sshd

The root ssh login will be disabled after the ssh service is
restarted.

How to separate files owned by a specific user in Linux

Muhammad Ali Ahmed — Fri, 23 Aug 2024 07:32:13 +0000

## In this post we will learn how we can separate files owned by a specific user while maintaining the directory structure in Linux

1. Locate files owned by specific users:

user find command to find files

find /home/usersdata -type f -user ali

Replace /home/usersdata with the directory where you want to search for files

This command will find all files owned by user ali excluding directories.

2. Install Rsync:

To install it
for centos

sudo yum update
sudo yum install rsync

for ubuntu

sudo apt update
sudo apt install rsync

3. Copy Files While Preserving Directory Structure

You can use rsync to copy files while preserving directory structure

rsync -av --files-from=<(find /home/usersdata -type f -user ali)/ /media

Explanation:

rsync -av: Syncs files in "archive" mode, which preserves permissions, timestamps, etc., and provides verbose output.
--files-from=<(find /home/usersdata -type f -user ali): This specifies the list of files to copy, generated by the find command.
/: The source directory (root) to consider the paths relative to.
/media: The destination directory where the files should be copied.

You can also write the list of files to a temporary file and then use rsync

find /home/usersdata -type f -user ali > /tmp/ali_files.txt
rsync -av --files-from=/tmp/ali_files.txt / /media
rm /tmp/ali_files.txt

Forem: Muhammad Ali Ahmed

How to disable root ssh login in Linux

It is important to understand why it is important to disable root ssh login in Linux

How to separate files owned by a specific user in Linux