How to replace master branch in Git, entirely, from another branch? [duplicate]

Question

I have two branches in my Git repository:

1. master
2. seotweaks (created originally from master)

I created seotweaks with the intention of quickly merging it back into master. However, that was three months ago and the code in this branch is 13 versions ahead of master.

It has effectively become our working master branch as all the code in master is more or less obsolete now.

Very bad practice I know, lesson learned.

Do you know how I can replace all of the contents of the master branch with those in seotweaks?

I could just delete everything in master and merge, but this does not feel like best practice.

Tiedeman

Also, this question is better worded and is missing the confusion caused by the "Extra" comment added to the question after answers had started. – Gschu

There is a simple way using checkout, if and only if you are not worried about commit histories of seotweaks. Switch to master branch first, then run, git checkout seotweaks -- * then run, git commit -m "Replaced contents of master with seotweaks" finally run git push – Halvorson

Answer 1

You should be able to use the “ours” merge strategy to overwrite master with seotweaks like this:

git checkout master
git pull
git checkout seotweaks
git merge -s ours master
git checkout master
git merge seotweaks

The first two steps are a useful precaution to ensure your local copy of master is up-to-date. The result should be that your master is now essentially seotweaks.

(-s ours is short for --strategy=ours)

From the docs about the 'ours' strategy:

This resolves any number of heads, but the resulting tree of the merge is always that of the current branch head, effectively ignoring all changes from all other branches. It is meant to be used to supersede old development history of side branches. Note that this is different from the -Xours option to the recursive merge strategy.

Update from comments: If you get fatal: refusing to merge unrelated histories, then change the second line to this: git merge --allow-unrelated-histories -s ours master

Astilbe

@Joel Berger, the recursive merge options will mix the two branches, favoring "theirs" or "ours" only on conflict. So you'll get changes from both branches. – Astilbe

This isn't working for me. When I do "git merge -s ours master" from the other branch, I get "Already up-to-date." Anything else I can try? – Selenaselenate

@Selenaselenate It's probably not an error: https://mcmap.net/q/13157/-git-merge-reports-quot-already-up-to-date-quot-though-there-is-a-difference – Astilbe

Since I am working on remote branches, I need to push after every merge? – Cosma

I ran into the exact same problem the original posted did and this approach replaced master with my desired branch within 2 minutes. Thank you. – Douglassdougy

the rename strategy posted by @ZelluX below better solves this problem. This answer will just merge a cleaned up branch on top of your existing master – Tricycle

@Astilbe Is there any advantage to this approach than ZelluX's method of renaming the branches? This one looks rather misleading later on when you look at the merge, but perhaps the renaming approach has a disadvantage? – Hin

Other than VonC's answer, which raises some issues, you don't retain any non-conflicting changes from the old master when you rename. You may not mind this, depends on the situation. – Astilbe

I like this solution because it keeps changes locally to be verified before overriding master!!! – Booher

Why are steps 3 and 4 needed when you already replaced the master branch ins step 1 and 2 – Tejeda

Worked for me. Remember to push both branches if you're trying to fix a remote repo like github or bitbucket. – Surat

This preserved all the commits on master :( Did I do it wrong? – Glacial

Did those steps - looked like did something locally, but it didn't. Luckily, I made a copy of my working dir first on the newer-branch - did a compare between that and the 'master' branch I supposedly updated. Nothing had been updated (typical git). Erased the files on the master-branch's dir (except .git), replaced it with the work in the dir with the newer-branch work, then git add-ed and committed - done. Lesson: make full-backups before 'git' anything. – Backscratcher

this does not work. I have to now resolve conflicts. Does not replace master. No different then merging 2 branches. – Pachydermatous

this would merge master into your branch ?? which is not what you want - you want to entirely replace master with another branch - or did I misunderstand ? – Cufic

I did this and did git push after. Effectively the master commits disappeared and was subsituted by the branches commits. IS there a way to reverse these commands? – Whensoever

@Whensoever you can see if you can revert to a previous state using reflog. See gitready.com/intermediate/2009/02/09/… – Astilbe

@Selenaselenate after renaming, simplest solution - push your local develop branch "master" to a remote branch "master" git push origin master:master stackoverflow.com/questions/2936652/… – Vaporizer

This approach worked great for me. We had a beta branch that was being treated as master, and a master branch that hadn't been touched in over a year. The only thing i did a little different was a git push before i merged beta into master. "git checkout beta" -> "git merge -s ours master" -> "git push" -> "git checkout master" -> "git merge beta" -> "git push" – Tetradymite

Most simply, assuming you do not care about losing master you could run git push -f origin seotweaks:master – Tacmahack

To avoid the need for a commit message: git merge -s ours --no-commit master – Brathwaite

When I do the second step I get fatal: refusing to merge unrelated histories. What do I do now? – Nich

But why is the merge commit message Merge branch 'master' into other instead of Merge branch 'other' into master? And why is this commit on both of the branches? It doesn't make sense for the merge to be on the other branch, as this branch should be the one that gets merged in master. – Endoenzyme

From what I understand, this actually merged the master branch into the other branch, and then fast-forwards the master branch. – Endoenzyme

If you get fatal: refusing to merge unrelated histories, then change the second line to this: git merge --allow-unrelated-histories -s ours master – Retention

Does this approach preserve the history of the original master? – Krafftebing

It is still merging 2 branches histories... I want to replace master entirely with seotweaks... – Rios

This can not be the answer, that is the answer https://mcmap.net/q/12853/-how-to-replace-master-branch-in-git-entirely-from-another-branch-duplicate – Todd

Not a good answer. This will still merge changes from master into your new branch and have unpredictable results. It's best to do the rename as stated below. – Woodberry

Still don't get how this thing works, lol. After first merge the seotweaks actually stays the same and master is the same. So after second merge master should contain both changes, isn't it? Does that last merge commit negate the master changes? – Redfin

Type :q then press enter to save the commit file after git merge -s ours master. – Colligan

git-scm.com/docs/git-merge#Documentation/git-merge.txt-ours . It will not work always, to quote the source Changes from the other tree that do not conflict with our side are reflected in the merge result. It did not work for me, as I had cleanly merging commits in my branch which was being overwritten. – Silky

@Silky Your quote is from the recursive ours which is different. Look a bit further down for the documentation about only ours option. – Benzoate

Worked really well for me. Just had to remember that my 'master' branch was named 'main'. – Hartmann

Don't forget to git push at the end – Restitution

Answer 2

What about using git branch -m to rename the master branch to another one, then rename seotweaks branch to master? Something like this:

git branch -m master old-master
git branch -m seotweaks master
git push -f origin master

This might remove commits in origin master, please check your origin master before running git push -f origin master.

Stull

Sorry, when I run this, the changes happen only locally. How can I get this to effect the remote branches? Thanks – Tiedeman

@Jason: Try git push -f origin master – Cavorelievo

This is probably the best way to do a forced update after ensuring your master can be completely replaced – Vesical

you can just do it in two steps: git branch -m oldbranch newbranch; git checkout mynewmaster; git checkout -b master; .... well, two anyway :-) – Huckaback

It might be worth explaining that this answer possibly removes commits that were in the original master branch. While ergosys' solution does a proper merge and so retains all history in master. – Marshmallow

Crap I just lost all commits in the original master. – Daytime

I also found this: https://mcmap.net/q/13159/-hard-merging-in-git using theirs – Kaiser

@Daytime you can do git checkout old-master && git push origin old-master to create a branch with the old master. – Wallpaper

Finalize with git push origin :seotweaks to remove the old ref from origin – Vulgarism

If you use this method and want to keep both branches (for example if you wanted to force push code from staging to replace master, but want to keep both branches after), just rename both branches to their original names after force push, and right after that do git checkout master and run git fetch --all and git reset --hard origin/master. This will force your local master history to align with remote's. – Mimimimic

This worked on gitlab. You have to run following before you do this. git checkout seotweaks – Catherine

This doesn't actually work...Just really messed up my repo – Cosma

downvote for just renaming branches not merging – Pyrometer

This is what I was looking for, to actually replace master in its entirety instead of merging (and the title does ask "How to replace master branch"). But instead of the final git push -f origin master I did instead git branch -u origin/master to set the upstream. In my case the changes to remove were not in the remote. – Unvoice

@Unvoice brings up a good point, to really do this you need to add git branch -u origin/master to the mix if the original branch is already tracked by a remote. – Pearman

Now after following the answer I'm left with master & old-master on my local and origin/seotweaks & origin/master on my remote. I want to keep both branches in both local and remote. How do I rename the branches and align them to track each other. I'm new to git, help me out with exact commands. THank you. – Adao

Answer 3

You can rename/remove master on remote, but this will be an issue if lots of people have based their work on the remote master branch and have pulled that branch in their local repo.
That might not be the case here since everyone seems to be working on branch 'seotweaks'.

In that case you can:
git remote --show may not work. (Make a git remote show to check how your remote is declared within your local repo. I will assume 'origin')
(Regarding GitHub, house9 comments: "I had to do one additional step, click the 'Admin' button on GitHub and set the 'Default Branch' to something other than 'master', then put it back afterwards")

git branch -m master master-old  # rename master on local
git push origin :master          # delete master on remote
git push origin master-old       # create master-old on remote
git checkout -b master seotweaks # create a new local master on top of seotweaks
git push origin master           # create master on remote

But again:

• if other users try to pull while master is deleted on remote, their pulls will fail ("no such ref on remote")
• when master is recreated on remote, a pull will attempt to merge that new master on their local (now old) master: lots of conflicts. They actually need to reset --hard their local master to the remote/master branch they will fetch, and forget about their current master.

---

Update/Note 2022:

• master would nowodays be named main
• git checkout is obsolete since Git 2.23 (Q3 2019): use git switch for branch operation.

    git branch -m main main-old  # rename main on local
    git push origin :main          # delete main on remote
    git push origin main-old       # create main-old on remote
    git switch -c main seotweaks # create a new local main on top of seotweaks
    git push origin main           # create main on remote

Haydon

Thanks for the detailed response, when I run 'git push remote :master' I get an error - 'remote' does not appear to be a git repository. – Tiedeman

@Jason: I changed that to 'origin' which might be the default name given to your remote repo. – Haydon

@VonC: I'm trying to do that on git-hub repository, but when trying to perform 'git push origin :master' I get a message '[remote rejected] master (deletion of the current branch prohibited)'. As for why I'm doing that... basically I severely mixed up things, importing two times the same patches through github interface and command line push, then getting everything back to work by manual merge. After that I also created another branch with a clean history, but too late... anyway. As it's on my personal experimental repository I should be the only one impacted. – Golightly

@kriss: GitHub will refuse by default any push rewriting/removing history, unless you force the push: git push -f origin :master. – Haydon

thanks this was a big help; I had to do one additional step, click the 'Admin' button on github and set the 'Default Branch' to something other than 'master', then put it back afterwards – Endoparasite

@house9: good point. I have edited my answer to include that step. – Haydon

Answer 4

Since seotweaks was originally created as a branch from master, merging it back in is a good idea. However if you are in a situation where one of your branches is not really a branch from master or your history is so different that you just want to obliterate the master branch in favor of the new branch that you've been doing the work on you can do this:

git push [-f] origin seotweaks:master

This is especially helpful if you are getting this error:

! [remote rejected] master (deletion of the current branch prohibited)

And you are not using GitHub and don't have access to the "Administration" tab to change the default branch for your remote repository. Furthermore, this won't cause down time or race conditions as you may encounter by deleting master:

git push origin :master

Helms

Does not work on Heroku: ! [rejected] <new_branch> -> master (non-fast-forward) error: failed to push some refs to '<some_git>.git' – Tucana

git push -f origin seotweaks:master worked for me – Daune

This was by far the easiest way for me to get extensive changes on a working branch, with many difficult conflicts (due to folders being deleted and renamed), back onto master. I don't know if this is appropriate for every case (probably not), but it totally worked for me just getting everything off a branch I was done with back onto master (the working branch remains after the operation, but both branches appear to now have the same commits). – Cleocleobulus

How does the master git history looks like after force push? Does it overwrite all files on master even when they weren't changed on seotweaks? – Rios

Answer 5

I found this to be the best way of doing this (I had an issue with my server not letting me delete).

On the server that hosts the origin repository, type the following from a directory inside the repository:

git config receive.denyDeleteCurrent ignore

On your workstation:

git branch -m master vabandoned                 # Rename master on local
git branch -m newBranch master                  # Locally rename branch newBranch to master
git push origin :master                         # Delete the remote's master
git push origin master:refs/heads/master        # Push the new master to the remote
git push origin abandoned:refs/heads/abandoned  # Push the old master to the remote

Back on the server that hosts the origin repository:

git config receive.denyDeleteCurrent true

Credit to the author of blog post http://www.mslinn.com/blog/?p=772

Meredithmeredithe

For me master branch was the default branch so I changed default branch as 'develop' branch and deleted master branch and created again master from desired branch. Later if you want you can make 'master' branch again your default branch. – Jaramillo

The link is broken, "Access Denied". – Emileemilee

Shame. I think the blogs do exist on his site still. Just a broken link :( – Meredithmeredithe

It changed. Now it shows an index of posts (and they seem to be accessible). – Emileemilee