github ssh login.md

gistfile1.md

Perfect, here's your setup with your exact details filled in:

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1. Generate the key pair

ssh-keygen -t ed25519 -C "roopkt@gmail.com"

• Press Enter to accept the default location (~/.ssh/id_ed25519)
• Set a passphrase (recommended) or press Enter to skip

Creates two files:

File	What it is	Share it?
~/.ssh/id_ed25519	Private key	❌ NEVER share
~/.ssh/id_ed25519.pub	Public key	✅ Upload to GitHub

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2. Start ssh-agent and add your key

eval "$(ssh-agent -s)"
ssh-add --apple-use-keychain ~/.ssh/id_ed25519

(On Linux, just use ssh-add ~/.ssh/id_ed25519)

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3. Copy the PUBLIC key

pbcopy < ~/.ssh/id_ed25519.pub

It looks like: ssh-ed25519 AAAAC3Nza... roopkt@gmail.com

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4. Add it to GitHub (account: rupeshtiwari)

1. Go to https://github.com/settings/keys (make sure you're logged in as rupeshtiwari)
2. Click "New SSH key"
3. Fill in:
   • Title: MacBook - Rupesh
   • Key type: Authentication Key
   • Key: paste (Cmd+V)
4. Click "Add SSH key"

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5. Test it

ssh -T git@github.com

Type yes to confirm the fingerprint the first time. Success:

Hi rupeshtiwari! You've successfully authenticated, but GitHub does not provide shell access.

Seeing your username rupeshtiwari there confirms it worked.

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6. Use SSH with your repos

Clone your Pluralsight repo over SSH:

git clone git@github.com:rupeshtiwari/pluralsight-designing-data-systems-llms.git

Switch an existing HTTPS repo to SSH:

git remote set-url origin git@github.com:rupeshtiwari/<repo-name>.git

Verify it switched:

git remote -v

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Here's your ~/.ssh/config setup so your personal GitHub key stays cleanly separated from any work keys.

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1. Create (or edit) your SSH config

touch ~/.ssh/config
chmod 600 ~/.ssh/config
open -e ~/.ssh/config    # opens in TextEdit; or use: nano ~/.ssh/config

2. Add this block

# ---- Personal GitHub (rupeshtiwari / roopkt@gmail.com) ----
Host github-personal
    HostName github.com
    User git
    IdentityFile ~/.ssh/id_ed25519
    IdentitiesOnly yes
    AddKeysToAgent yes
    UseKeychain yes

If you ever add a work key later, you'd drop in a second block with its own alias and IdentityFile, so the two never clash:

# ---- Work GitHub (example, add only if needed) ----
Host github-work
    HostName github.com
    User git
    IdentityFile ~/.ssh/id_ed25519_work
    IdentitiesOnly yes

IdentitiesOnly yes is the important line: it forces SSH to use only the key you named for that host, instead of throwing every key in your agent at GitHub (which causes the "too many authentication failures" error).

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3. How you use the alias

Because the host alias is github-personal, your clone/remote URLs use that instead of github.com:

# Clone
git clone git@github-personal:rupeshtiwari/pluralsight-designing-data-systems-llms.git

# Switch an existing repo to use the personal alias
git remote set-url origin git@github-personal:rupeshtiwari/<repo-name>.git

Test it:

ssh -T git@github-personal

Success:

Hi rupeshtiwari! You've successfully authenticated, but GitHub does not provide shell access.

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4. Match your commit identity for personal repos

So commits attribute to your personal account, set this per repo (not global, since you're on the Amazon machine):

cd <your-repo>
git config user.name "rupeshtiwari"
git config user.email "roopkt@gmail.com"

Verify:

git config user.email    # should print roopkt@gmail.com

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Mental model

• Host github-personal is just a nickname. When you type git@github-personal:..., SSH looks up that block, connects to the real github.com, and uses only your personal key.
• Add a second Host block per additional account. The alias in the URL is what picks the key. No clashing, no wrong-account commits.

That's the whole thing. Once you clone with the github-personal alias, git push / git pull just work with no password.

Here's the one-liner to confirm exactly which key GitHub is accepting:

ssh -vT git@github-personal 2>&1 | grep -E "Offering|Server accepts|Authenticated|Hi "

Run it and you'll see output like:

debug1: Offering public key: /Users/rupeshti/.ssh/id_ed25519 ED25519 SHA256:xxxx...
debug1: Server accepts key: /Users/rupeshti/.ssh/id_ed25519 ED25519 SHA256:xxxx...
Authenticated to github.com
Hi rupeshtiwari! You've successfully authenticated...

How to read it:

• Offering public key: → the key your machine tried
• Server accepts key: → the key GitHub actually accepted (this is the one in use)
• Hi rupeshtiwari! → confirms it mapped to your personal account

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Handy variations

See every key your agent is throwing at GitHub (diagnoses "too many authentication failures"):

ssh-add -l

Full verbose trace if a push ever gets rejected:

GIT_SSH_COMMAND="ssh -v" git push 2>&1 | grep -E "Offering|accepts|denied"

Confirm a repo is using the right alias + identity:

git remote -v && git config user.email

Remote should show git@github-personal:... and email should be roopkt@gmail.com.

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That's your complete SSH setup: key generated, agent configured, ~/.ssh/config with isolated personal host, commit identity set, and now a verification one-liner. Once Server accepts key shows your id_ed25519, you're fully wired — git push/pull will work passwordless with no account clashing.