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Openbsd

How to disable ssh password login on Linux to increase security

I want to disable ssh clients from accessing using the password and only allow ssh login using SSH keys. How do I disable password authentication for SSH on Linux operating systems?
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How to install denyhosts on Ubuntu Linux 16.04 LTS ( intrusion prevention security tool )

I host my blog in cloud server, and I set up ssh to manage my Ubuntu Linux 16.04 LTS server. However, I noticed lots of break in and brute-force attacks on my ssh server? How can I stop hacking attempts into my system?
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Linux/Unix: Force ssh client to use only password auth authentication when pubkey auth configured

I configured and use my openssh server to accept only public key based authentication. I need to test if my server accepting password. How to allow ssh client to use only password auth when pubkey auth configured?
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How to fix: MacOS keep asking passphrase for ssh key after upgrade or reboots

I recently upgraded my MacOS Sierra and now ssh command keep asking for passphrase as follows when I try to login to my remote Linux/Unix server:
      Enter passphrase for key ‘/Users/vivek/.ssh/id_ed25519’:
How do I fix MacOS Sierra upgrade that keep breaking ssh keys in terminal?
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How to change the ssh port on Linux or Unix server

I am a new Linux/Unix server admin. How do I change the SSH Port for my Linux or Unix server using command line option?
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How to apply patches on OpenBSD system/kernel and packages easily

I am a regular Linux system user. In Linux (especially CentOS), I am used to applying updates a few times a week using yum command, but how do I do that on my OpenBSD severer? How do I apply updates on OpenBSD operating system?
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How to upgrade OpenSSH 7.0 to 7.2 on a OpenBSD Unix and Linux

OpenSSH version 7.2 has been released. How do I install or upgrade my existing OpenSSH version to 7.2 on a OpenBSD unix operating system?
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The OpenSSH project released an ssh client bug info that can leak private keys to malicious servers. A man-in-the-middle kind of attack identified and fixed in OpenSSH are dubbed CVE-2016-0777 and CVE-2016-0778. How do I fix OpenSSH’s client vulnerability on a Linux or Unix-like operating system?
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How To SSH Run Multiple Command On Remote Machine And Exit Safely

I have a backup sync program on local server. I have an ssh password less login set up, and I can run commands on an external server in bash script doing:

ssh root@server2 "sync; sync; /sbin/shutdown -h now"

How do I run multiple commands in bash on a remote Unix or Linux server? What is the best way to SSH in and run various unix commands in a bash shell?
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SSH ProxyCommand example: Going through one host to reach another server

How do I use and jump through one server to reach another using ssh on a Linux or Unix-like systems? Is it possible to connect to another host via an intermediary so that the client can act as if the connection were direct using ssh?
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