Force your forked repo to be the same as upstream.

fork forced sync

git fetch upstream
git reset --hard upstream/master

Keep in mind, that this makes your repo look exactly like upstream - if you have commits, they will be eaten! If you want to update to upstream (but still keep your commits), you want git merge upstream/master. If you want to start a new patch based on upstream, the best way to do it is git checkout -b my-new-feature upstream/master

Of course, this all expects you have a remote named upstream, which you can create by doing git remote add upstream https://[upstream guy's repo url]

(Just to clarify, the term 'upstream' means the person you forked from)

[danny@server01 kloxo]$ git fetch upstream
[danny@server01 kloxo]$ git reset --hard upstream/dev
fatal: ambiguous argument 'upstream/dev': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git [...] -- [...]'

And now?

So this works great locally, but how can I get my github repo master branch to be the same as locally/upstream??

@pepa65
git push origin master --force

complete git commands would be like this:

git remote add upstream https://github.com/some_user/some_repo
git fetch upstream
git checkout master
git reset --hard upstream/master  
git push origin master --force

worked for me..thnx

@JerryGoyal PRAISE YOU

see also git - Clean up a fork and restart it from the upstream - Stack Overflow

@JerryGoyal thank you kind sir

👍

Why not just delete the fork and start over?

@JerryGoyal, Thank you!

@jtr13 might have Github issues you want to keep around

So how about the opposite situation?

What if the history was changed on a fork but it needs to be asserted as the upstream master?
ie, the error: "There isn’t anything to compare." A:master and B: "are entirely different commit histories."

Precondition: Working on the fork

git fetch origin
git checkout master
git reset --hard origin/master
git remote add upstream https://github.com/some_user/A
git push upstream master --force

Would this have expected results?

git push --force is a required step too to update your remote i.e. origin/master after the hard reset

Works like a charm. Thanks!

This is so great, thank you! @JerryGoyal

what if there are new files in my commit that I want to keep, but changes the upstream made to files that I already have that I also want. When I try to merge upstream, I receive an error: files would be overwritten by merge. But I want them to be overwritten.

can we do this from the GitHub UI?

How can I force users to pull from upstream after a major upgrade of the source code. I have PR validation in place (Jenkins) and they are using the old validation code (python).. ?

Works perfectly. Thanks for the tip.

you may need to also push tags

git push --tags

other variations:

git reset --hard upstream/master
git reset --hard upstream/main
git reset --hard upstream/development

👍

complete git commands would be like this:

git remote add upstream https://github.com/some_user/some_repo
git fetch upstream
git checkout master
git reset --hard upstream/master  
git push origin master --force

Perfect! Thank you!

So this works great locally, but how can I get my GitHub repo master branch to be the same as locally/upstream??

This is possible with a one-liner that doesn't require downloading anything...

For anyone interested in syncing your GitHub-hosted fork directly (without cloning locally first) you can do this using the GitHub CLI:

gh repo sync owner/cli-fork -b BRANCH-NAME