A sign-off message in the following format appear on each commit in the pull request

sign-off.md

If it requires a sign-off message in the following format appear on each commit in the pull request:

This is my commit message

Signed-off-by: Random Developer <[email protected]>

The text can either be manually added to your commit body, or you can add either -s or --signoff to your usual git commit commands.

Creating your signoff

Git has a -s | --signoff command-line option to append this automatically to your commit message:

git commit --signoff --message 'This is my commit message'

git commit -s -m "This is my commit message"

This will use your default git configuration which is found in .git/config and usually, it is the username systemaddress of the machine which you are using.

To change this, you can use the following commands (Note these only change the current repo settings, you will need to add --global for these commands to change the installation default).

Your name:

git config user.name "FIRST_NAME LAST_NAME"

Your email:

git config user.email "[email protected]"

How to amend a sign-off

If you have authored a commit that is missing the signed-off-by line, you can amend your commits and push them to GitHub

git commit --amend --signoff

If you've pushed your changes to GitHub already you'll need to force push your branch after this with git push -f.

Source: https://github.com/pi-hole/docs/blob/master/docs/guides/github/how-to-signoff.md