Ubuntu Linux setup basics

For username "foo":

$ adduser foo

$ passwd foo

$ sudo usermod -aG sudo foo

$ mkdir -p /home/foo/.ssh

$ cat the_public_key.pem >> /home/foo/.ssh/authorized_keys

$ chown -R foo:foo /home/foo/.ssh

$ chmod 700 /home/foo/.ssh

$ chmod 600 /home/foo/.ssh/authorized_keys

Disable default account:

$ usermod -s /usr/sbin/nologin default_username

Notes:

Not useradd.
Even when logging in with just SSH key, user must have a password. It will only be used for sudo commands.

Sources:

https://unix.stackexchange.com/questions/210228/add-a-user-without-password-but-with-ssh-and-public-key

Sudoers basics

Batch deleting files in Windows

List all the jpg files:

dir /s *.jpg /b > jpgs.txt

Delete all the jpg files:

del /s /q /f /a *.jpg

Mac top

On a Mac, sort top output by %CPU, descending:

top -o -cpu

Jenkins admin notes

Some things to help on your Continuous Integration journey with Jenkins:

• Use  docker pull jenkins  for a quick start
• Security can be a bit fiddly to set up. Try these easy settings:
• Jenkins’ own user database
• Allow users to sign up
• Logged-in users can do anything
• There is a Role-Based Strategy plugin for more advanced use
• If you accidentally lock yourself out, edit  $JENKINS_HOME/config.xml  to say false and restart Jenkins
• To see a list of failing tests, configure a Post-build action for  "Publish JUnit test result report"

-- Jenkins ver. 1.642.2

Common admin tasks in phpBB 3

Change the author of a post:

• Click on the post
• Click on the "Moderator Control Panel" link in the top left
• Click on the "Post details" link on the right-hand side (note: It might look like a triangle with a question mark in it)
• Scroll down to the bottom of the post, and you will see a drop-down menu to change the poster.