---
title: "SSH Key Management FAQ"
description: "Short answers about SSH keys in TIR, each linking to the full page."
content_type: "faq"
product: "ssh-keys"
platform: "TIR"
url: "/tir/ssh-keys/faq/"
---

# SSH Key Management FAQ

## Why can I not delete an SSH key?

You can delete a key once it is off every instance, virtual machine, and training cluster. Select the
key's name to see what uses it, take the key off those resources, then delete it. See
[Delete an SSH key](/tir/ssh-keys/how-to/delete-an-ssh-key/).

## Are SSH keys per project?

No. Your SSH keys belong to you and show in every project.

## I added a key in MyAccount. Why is it not in TIR?

On the **SSH Keys** page, open the **Add Key** menu and select **Sync from MyAccount** to copy the keys of your MyAccount default project. See
[Sync SSH keys](/tir/ssh-keys/how-to/sync-ssh-keys-from-myaccount/).

## Does TIR keep the private key of a key I create in the browser?

No. Download it with **Download .pem file** when you create it. A lost private key is gone for
good, so create a new key if that happens. See [Create a key in the browser](/tir/ssh-keys/how-to/create-an-ssh-key-in-the-browser/).

## Can I use one key on several instances?

Yes. Your keys belong to you, so you can choose the same key on every instance, virtual machine, or training cluster you
create, in any project. See [Connect with an SSH key](/tir/ssh-keys/how-to/connect-with-an-ssh-key/).

## Which key types does TIR accept?

Ed25519, RSA, and ECDSA public keys. A public key starts with `ssh-ed25519`, `ssh-rsa`, or `ecdsa-sha2`.
See [What a valid key looks like](/tir/ssh-keys/how-to/add-an-ssh-key/#what-a-valid-key-looks-like).

## Can I add several keys at once?

No. Add one key at a time; pasting more than one is refused. A key name can have up to 50 characters and
must differ from the names of your other keys. See [Add an SSH key](/tir/ssh-keys/how-to/add-an-ssh-key/).

## Which key type should I use?

Use `ed25519`. RSA 4096 is also a good choice. See
[How SSH keys work](/tir/ssh-keys/concepts/how-ssh-keys-work/).