Git推送至origin master遇publickey权限拒绝，如何重连GitHub？

Hey there, let's fix this git@github.com: Permission denied (publickey) headache once and for all—this is one of the most common GitHub SSH issues, and we can work through it step by step.

Step 1: Check if you already have an SSH key pair #

First, let's see if you've got existing SSH keys on your machine. Run this in your terminal:

ls -al ~/.ssh

Look for files like id_ed25519 (private key) and id_ed25519.pub (public key)—Ed25519 is the modern, recommended key type. If you don't see these, or only have older RSA keys, generate a new pair with:

ssh-keygen -t ed25519 -C "your_email@example.com"

Just press Enter through all prompts (you can set a passphrase if you want extra security, but it's optional).

Step 2: Ensure the SSH agent is running and your key is added #

SSH agent manages your keys in the background—let's make sure it's active and knows about your key:

1. Start the agent:

   eval "$(ssh-agent -s)"
   

2. Add your private key to the agent:

   ssh-add ~/.ssh/id_ed25519
   

   (If you're using an RSA key, replace id_ed25519 with id_rsa.)
   Pro tip: If you tried adding the key before and it didn't stick, run ssh-add -d ~/.ssh/id_ed25519 first to remove any old entries, then re-add.

Step 3: Add your public key to your GitHub account #

This is the most crucial step—GitHub needs to recognize your machine's public key:

1. Copy your public key to your clipboard:

   cat ~/.ssh/id_ed25519.pub
   

   Select and copy the entire output (it starts with ssh-ed25519 and ends with your email).
2. Log into GitHub, go to Settings > SSH and GPG keys > New SSH key.
3. Give it a descriptive title (like "My Work Laptop") and paste the copied key into the "Key" field. Click Add SSH key.

Step 4: Test the SSH connection #

Let's verify everything works before trying to push again:

ssh -T git@github.com

If you see a message like Hi [YourUsername]! You've successfully authenticated, but GitHub does not provide shell access., you're good to go!

Bonus Troubleshooting Tips (if the above steps don't work) #

• Check your remote repo URL: Run git remote -v—if your origin is using HTTPS instead of SSH, switch it with:

  git remote set-url origin git@github.com:YourUsername/YourRepoName.git
  

• Fix ~/.ssh/config issues: If you have a ~/.ssh/config file, make sure your GitHub entry looks like this (adjust the key path if needed):

  Host github.com
      HostName github.com
      User git
      IdentityFile ~/.ssh/id_ed25519
  

• Disable VPN/Firewall temporarily: Sometimes VPNs or strict firewalls block SSH connections to GitHub—try turning them off briefly to test.
• Confirm repo permissions: Double-check that your GitHub account has push access to the repo (you're either the owner or added as a collaborator with write permissions).

内容的提问来源于stack exchange，提问作者Batuhan Dogan