Question

I have several identities to work with github. They are managed via the .ssh/config file:

# This is the normal github account. We do not need this (it is the default),
#   but putting it here makes things more clear
Host github.com
     User           git
     HostName       github.com 
     IdentityFile   <rsa1>

# We use this fake host so that we can provide an alternative ssh keypair
Host github-2.com
     User           git
     HostName       github.com 
     IdentityFile   <rsa2>

I have verified that I am authorized with both accounts:

ssh -T [e-mail]
Hi user1! You've successfully authenticated, but GitHub does not provide shell access.

ssh -T [e-mail]
Hi user2! You've successfully authenticated, but GitHub does not provide shell access.

Now I go to my repo, and try to push to the remote a new branch

git push origin origin:refs/heads/testing
error: src refspec origin does not match any.
error: failed to push some refs to 'git@github-2:user2/repo.git'

The relevant section in my .git/config is:

[remote "origin"]
    fetch = +refs/heads/*:refs/remotes/origin/*
    url = [e-mail]:user2/repo.git

And I have this:

$ git remote -v
origin  [e-mail]:user2/repo.git (fetch)
origin  [e-mail]:user2/repo.git (push)

What could be going wrong?

Answer 1

I will put this here for reference, since I solved my issue: I know how, but I do not really know why.

I did a new clone of my repo. The .git/config was the same as my original one.
In this fresh copy, I have no push issues. Magic.