Fixing SSH setup for GitHub

TODO: collapasable, copyable, download, etc

I need help fixing my ssh setup for github. I have two github accounts. The secondary one... my identity is ozten. I have this config

# Default Deductive Github
Host github.com
  AddKeysToAgent yes
  UseKeychain yes
  IdentityFile ~/.ssh/id_ed25519

Host github.com-ozten
  HostName github.com
  User git
  IdentityFile ~/.ssh/id_ed25519_ozten```

If I do ```ssh github.com-ozten
PTY allocation request failed on channel 0
Hi austin-king! You've successfully authenticated, but GitHub does not provide shell access.```

I expect it to say "Hi ozten". What is wrong?The configuration you've shared indicates you're trying to use SSH to connect to two different GitHub accounts using distinct SSH keys. Your setup for the secondary account (`ozten`) looks mostly correct, but the fact that it authenticates you as `austin-king` suggests the key used is not exclusively associated with the `ozten` account on GitHub.

Here are a few things to check and steps to resolve the issue:

1. **SSH Key Association**: Ensure that the SSH key `~/.ssh/id_ed25519_ozten` is added to the SSH keys in the `ozten` GitHub account. Log into GitHub as `ozten`, navigate to "Settings" > "SSH and GPG keys" and confirm that the public key part of `id_ed25519_ozten` is listed there.

2. **SSH Agent**: If you're using an SSH agent (and your configuration suggests you might be, with `AddKeysToAgent yes`), ensure that the correct key is loaded and used. Sometimes, if you have multiple keys loaded into the SSH agent, it might use the first one that authenticates successfully with GitHub, which could be the key for `austin-king`. You can list the keys currently added to the agent with `ssh-add -l`.

3. **IdentityFile Configuration**: Your configuration looks correct, but ensure there are no typos in the path to the key file, and that the key file has the correct permissions (typically `600`, readable and writable only by the owner).

4. **Test SSH Configuration for ozten**: You can use the `-v` option with SSH to get verbose output, which can help debug which key is being offered and why it might fail. Try running `ssh -vT [email protected]` and look for lines indicating which identity file is being used.

5. **Exclusive Key Use**: To ensure that the correct key is used for each account, you might want to explicitly specify which identities should be tried for connections to `github.com`. This can be done by adding the `IdentitiesOnly yes` option to each `Host` block in your SSH config. This forces SSH to only use the key specified in the `IdentityFile` directive for each host:

    ```
    Host github.com
      AddKeysToAgent yes
      UseKeychain yes
      IdentityFile ~/.ssh/id_ed25519
      IdentitiesOnly yes

    Host github.com-ozten
      HostName github.com
      User git
      IdentityFile ~/.ssh/id_ed25519_ozten
      IdentitiesOnly yes
    ```

Applying these checks and modifications should help ensure that the correct SSH key is used for each GitHub account, resulting in the expected authentication message for `ozten`.ssh-add -l is missing my keyIf `ssh-add -l` does not list your key for the `ozten` account (`~/.ssh/id_ed25519_ozten`), it means the SSH agent is not aware of this key. You'll need to add it manually to the SSH agent to ensure it can be used for authentication. Here's how you can do it:

1. **Start the SSH Agent**: If the SSH agent is not running, you need to start it. You can start it by running:
   ```bash
   eval "$(ssh-agent -s)"

This command starts the SSH agent and sets the necessary environment variables for your current session.

2. Add Your SSH Key to the SSH Agent: Once the SSH agent is running, add your specific SSH key (id_ed25519_ozten) to the agent with the following command:

   ssh-add ~/.ssh/id_ed25519_ozten
   

   This command loads your private key into the SSH agent, allowing the SSH client to use it for authentication without having to specify it directly each time.

3. Verify Key Addition: After adding your key, you can verify it's listed in the agent by running ssh-add -l again. You should see your ~/.ssh/id_ed25519_ozten key listed among the keys managed by the SSH agent.

4. Persistent Addition Across Sessions: Depending on your system setup, you might need to add the key to the SSH agent each time you start a new session. To automate this, you can add the ssh-add command to your shell's startup script (e.g., ~/.bash_profile, ~/.bashrc, ~/.zshrc, etc.). Add the following line:

   ssh-add ~/.ssh/id_ed25519_ozten >/dev/null 2>&1
   

   This will ensure your key is automatically added to the SSH agent whenever you start a new shell session, reducing the need to manually add it each time.

After performing these steps, your SSH setup should recognize and use the correct key for your ozten GitHub account when you attempt to authenticate or perform operations requiring SSH access.

Fixing SSH setup for GitHub created at Tue Jan 20 1970 18:21:15 GMT+0000 (Coordinated Universal Time)