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Questions tagged [sshd]

sshd - OpenSSH SSH daemon

sshd (SSH Daemon) is the daemon program for ssh. Together these programs replace rlogin and rsh, and provide secure encrypted communications between two untrusted hosts over an insecure network.

253 questions
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4 answers

How do I force SSH to only allow users with a key to log in?

I tried following the instructions here: http://lani78.wordpress.com/2008/08/08/generate-a-ssh-key-and-disable-password-authentication-on-ubuntu-server/ to only allow users with a public key on the server to authenticate, but I can't get SSH to…
user193805
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4 answers

What does 'without password' mean in sshd_config file?

I just installed Ubuntu 14.04 on my server and I was setting up all my config files when I came across this in my sshd_config file: # Authentication: LoginGraceTime 120 PermitRootLogin without-password StrictModes yes This made me very worried. I…
John
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85
votes
6 answers

take changes in file sshd_config file without server reboot

I changed the configuration in: /etc/ssh/sshd_config but the changes were only applied after rebooting the server. How to apply changes without a reboot?
Maxim Yefremov
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45
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8 answers

SSH default port not changing (Ubuntu 22.10 and later)

I am on Ubuntu 22.10 and I cannot change SSH default port. I have tried the following: Edited /etc/ssh/sshd_config, left the default #Port 22 line but added Port 1234 below it. Then added allow rule for it in UFW using the command: sudo ufw allow…
Silently
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44
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2 answers

Unable to start sshd

I'm new to Ubuntu and trying to start sshd but having a lot of problems. I've tried uninstalling and reinstalling ssh by running sudo apt-get remove openssh-client openssh-server and sudo apt-get install openssh-client openssh-server. When I run…
dandelion
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36
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2 answers

SSH Server cannot be found - Even though installed

I have a machine running Ubuntu 18.04 LTS where I cannot seem to get SSH Server working. I installed SSHServer using: sudo apt install openssh-server but I am getting the following when I try to start and / or check the status: sudo systemctl start…
Alan
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35
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9 answers

How do I disable SSHD from starting automatically?

After installing openssh-server, the server start every time I boot. If I want it to be manual what do I need to do? In version 0.6.7+ of upstart I would add a "manual" stanza to the job file. 10.04 has upstart 0.6.5-8. What is the preferred way to…
komputes
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32
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2 answers

How to get the list of all users who can access a server via ssh?

How can I get the list of all the users who can ssh to a server via ssh username@server.domain ? Please note that I'm aware of this question and that is not doing what I want! If it helps the server has so many users in so many different groups and…
yukashima huksay
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30
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7 answers

tail: inotify cannot be used, reverting to polling: Too many open files

When I try to tail -f catalina.out, I get the error: tail: inotify cannot be used, reverting to polling: Too many open files I tried the answer in this post: Too many open files - how to find the culprit lsof | awk '{ print $2; }' | sort -rn |…
gbag
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26
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2 answers

Key based SSH login that requires both key AND password

My problem is : I developed successfully RSA Key based ssh login on board from system. When a client logs in for the first time, ask about private key and passphrase also which works fine. In second time login, ssh doesn't ask private key or…
Tejas Virpariya
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22
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How to block specific username from ssh?

I have testuser and I want that user to be able log-in locally, but not via ssh. How can I implement that?
Sergiy Kolodyazhnyy
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15
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4 answers

How to disable autostart of SSHD in Ubuntu 15.04

In older versions of Ubuntu I commented out the "start on ..." line in /etc/init/ssh.conf. This worked well, but not in Ubuntu 15.04.
Fango
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15
votes
2 answers

What does %h mean in SSHD configuration?

I'm setting up OpenSSH on a server and I've created my keys on my client, but I don't know where I'm supposed to put the public key on the host. I understand it needs to be added to the authorized_keys file, but where is the authorized keys file? In…
A. Franco
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14
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3 answers

How to remove legal notice from MOTD / Banner for non-root users

Problem: The following text is shown for all non-root users when logging in via SSH: The programs included with the Ubuntu system are free software; the exact distribution terms for each program are described in the individual files in…
Nicolai Fröhlich
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14
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3 answers

Granting a sftp user access to a /var/www directory

I've created a user and made his home directory /var/www/mysite/ftpdir I've also added a Match user entry for this user in sshd_config with a ChrootDirectory that points to /var/www/mysite I've restarted ssh to pick this up. When I log in with sftp…
hawkeye
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