SSH to use two-factor authentication using Google Authenticator on Debian or Ubuntu Server Rumi, November 19, 2023 A computer running Ubuntu 16.04 LTS or above A phone running Android or iOS A configured SSH connection You should understand the danger of stolen passwords. You don’t need to know what two-factor authentication is and how it works. 🙂 Installing and configuring required packages Start a terminal session and… Continue Reading
Enable Password based authenticaiton in OCI compute instance Rumi, May 13, 2023 If you want to use a password to access the SSH server, a solution for fixing the Permission denied error is to enable password login in the sshd_config file. To do this, open the file in a text editor. This example uses the nano editor: sudo nano /etc/ssh/sshd_config In the file, find… Continue Reading
SSH Key-Pair Authentication Rumi, September 3, 2022 Create Key-Pair by each user, so login with a common user on SSH Server Host and work like follows. # create key-pair debian@dlp:~$ssh-keygen Generating public/private rsa key pair. Enter file in which to save the key (/home/debian/.ssh/id_rsa): # Enter or input changes if you want Created directory ‘/home/debian/.ssh’. Enter passphrase… Continue Reading
SCP Command Syntax Rumi, March 14, 2019 Before going into how to use the scp command, let’s start by reviewing the basic syntax. The scp utility expressions take the following form: scp [OPTION] [user@]SRC_HOST:]file1 [user@]DEST_HOST:]file2 OPTION – scp options such as cipher, ssh configuration, ssh port, limit, recursive copy ..etc [user@]SRC_HOST:]file1 – Source file. [user@]DEST_HOST:]file2 – Destination… Continue Reading
SSH Tunnel on PuTTY Rumi, January 5, 2019 Most of you have probably used a tunnel with an SSH connection. What you probably weren’t aware of is that you can use a dynamic tunnel to access all remote infrastructure. Furthermore, you can specify a port and a destination IP to have direct access. This process is achieved through… Continue Reading
How to Update SSH & MOTD Banner on CentOS 6 Rumi, December 7, 2015December 7, 2015 For legal reasons, Some people need to display a warning banner on their Linux machine before login so that a person requires to acknowledge the contents of the banner before entering the password. To do this, edit a/etc/issue.net file and fill it with the desired context. Edit the /etc/issue.net file: sudo… Continue Reading
Reinstall OpenSSH Server Rumi, June 21, 2014 First if you have any pre-installed SSH server that has gone bad, remove it- on Redhat Architechture Type the following commands as the root user: # chkconfig sshd off # service sshd stop # yum erase openssh-server You need to edit and update firewall rules that allows inbound connections to… Continue Reading
SSH Public key based authentication Rumi, June 9, 2014September 3, 2017 Method-1: Create the cryptographic Key on FreeBSD / Linux / UNIX workstation, enter: ssh-keygen -t rsa Assign the pass phrase (press [enter] key twice if you don’t want a passphrase). It will create 2 files in ~/.ssh directory as follows: ~/.ssh/id_rsa : identification (private) key ~/.ssh/id_rsa.pub : public key Use… Continue Reading
Reinstall Openssh server on Debian 6/7 Rumi, June 6, 2014 Linux: Debian / Ubuntu Linux Remove SSHD Server Type the following commands: # apt-get –purge remove openssh-server Now reinstall the openssh again using- # apt-get install openssh-server Voila Src: http://www.cyberciti.biz/faq/howto-unix-linux-remove-delete-opensshd-server/ Continue Reading