Differences

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--- howto:setup-sscs-linux-account-public-keys [2025/03/10 20:24] – created jnilsson
+++ howto:setup-sscs-linux-account-public-keys [2025/07/17 18:32] (current) – [How to: Disable SSH Password Authentication] jnilsson
@@ Line 7: / Line 7: @@
 ===== One-stop script to create the sscs account =====
-You can simply copy and paste the below code:
+You can simply copy and paste the below code to download a script that we've set up for this purpose and execute it with sudo:
+<code>
+curl -O -L https://sites.socsci.uci.edu/~jnilsson/sscs/setup-sscs-account.sh
+chmod +x ./setup-sscs-account.sh
+sudo ./setup-sscs-account.sh
+</code>
+Or if you prefer to run commands yourself, these are the equivalent commands:
 <file>
 SSCS_HOME=/home/sscs
 sudo useradd -c "Computing Services" -m -d $SSCS_HOME -s /bin/bash sscs
-echo "sscs    ALL=(ALL)   ALL" | sudo tee -a /etc/sudoers.d/sscs
+echo "sscs    ALL=(ALL)   ALL" | sudo tee /etc/sudoers.d/sscs > /dev/null
 sudo mkdir -p $SSCS_HOME/.ssh
 sudo chmod 700 $SSCS_HOME/.ssh
 sudo touch $SSCS_HOME/.ssh/authorized_keys
 sudo chmod 600 $SSCS_HOME/.ssh/authorized_keys
-echo "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIPWfC91AllbEn9VYT9a0838A/55rWtrSY/dm48fedc38 jnilsson@C21121501.local" | sudo tee -a $SSCS_HOME/.ssh/authorized_keys
+sudo chown -R sscs:sscs $SSCS_HOME/.ssh
+echo "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIPWfC91AllbEn9VYT9a0838A/55rWtrSY/dm48fedc38 jnilsson@storgy.local" | sudo tee -a $SSCS_HOME/.ssh/authorized_keys
+echo "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIDoygQr0UQLtpguLWJYiEBZWXUFEkUXVacE6sBZtn/6Z jnilsson@devjpn" | sudo tee -a $SSCS_HOME/.ssh/authorized_keys
+echo "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIKH3jg7avVgdyx1jltUp9nJ02DOE9XH3hfcGBQI6KrVs sscs@gunship" | sudo tee -a $SSCS_HOME/.ssh/authorized_keys
+echo "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIBqAc8VSY9DFEzzumkn1d2S1ytpYOWHSJkbOWN1HjFQR sscs@crateria" | sudo tee -a $SSCS_HOME/.ssh/authorized_keys
+echo "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIC4u9RrufB93/AS2lsBVet4+U5rizO8noDKTSHhcLmli justip6@Zaire" | sudo tee -a $SSCS_HOME/.ssh/authorized_keys
+echo "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIErG9uQN2VUNqIjNowRw1J18T8dORd2HhJi3zl9Vs7+t justip6@zeon.ss2k.uci.edu" | sudo tee -a $SSCS_HOME/.ssh/authorized_keys
+echo "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIMtdfuw5hq6naiRnVCAKEUhpYTazWC5WE7rxCcXLN/cU lhtran@bahamut-zero.local" | sudo tee -a $SSCS_HOME/.ssh/authorized_keys
+echo "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIK5DC1gTDzQtcNhvoCkgUzsf7ntvP/Ldac3EAgZ9Y/yc soceco\lmonzon@TECDSHHS9WX3" | sudo tee -a $SSCS_HOME/.ssh/authorized_keys
 </file>
-Or download and run the script that we've set up to do this for you:
+If you don't want the home directory to be /home/sscs, you can easily set your own SSCS_HOME variable to whatever location you choose and then copy/paste the rest of the commands. Or if you download the ''setup-sscs-account.sh'' script and you want to change the location of the sscs account home directory, modify the script accordingly before executing it.
-<code>
-curl -O -L https://sites.socsci.uci.edu/~jnilsson/sscs/setup-sscs-account.sh
-sudo ./setup-sscs-account.sh
+===== How to: Disable SSH Password Authentication ======
+Disabling Password Authentication is generally as simple as setting the option ''PasswordAuthentication no'' in the /etc/ssh/sshd_config file and then restarting the sshd service.
+However, we've discovered that some linux distributions add another configuration file **/etc/ssh/sshd_config.d/50-cloud-init.conf** which contains ''PasswordAuthentication yes'' to force password authentication to be enabled.
+Therefore, the easiest way to universally disable password authentication is to create a new file that sorts lexicographically before any other files that might be created in there, such as **00-disable-password-auth.conf**:
+<file>
+PasswordAuthentication no
+</file>
+After setting the ''PasswordAuthentication'' option to ''no'' you must reload the sshd daemon to get this setting to take effect:
+  * on Debian/Ubuntu:<code>
+sudo systemctl reload ssh
+</code>
+  * on RHEL/Rocky:<code>
+sudo systemctl reload sshd
 </code>
-If you don't want the home directory to be /home/sscs, you can easily set your own SSCS_HOME variable to whatever location you choose and then copy/paste the rest of the commands. Or if you download the ''setup-sscs-account.sh'' script and you want to change the location of the sscs account home directory, modify the script accordingly before executing it.