How can I access my SSH public key? Then you've to generate your RSA key by ssh-keygen first. On Mac/unix and Windows: ssh-keygen then follow the. Apr 02, 2019 SSH keys offer a highly secure manner of logging into a server with SSH as against mere dependence on a password. While a password stands the risk of being finally cracked, SSH keys are rather impossible to decipher using brute force.
-->With a secure shell (SSH) key pair, you can create virtual machines (VMs) in Azure that use SSH keys for authentication, eliminating the need for passwords to sign in. This article shows you how to quickly generate and use an SSH public-private key file pair for Linux VMs. You can complete these steps with the Azure Cloud Shell, a macOS or Linux host, the Windows Subsystem for Linux, and other tools that support OpenSSH.
Note
Mac Generate 4096 Ssh Key Mac
VMs created using SSH keys are by default configured with passwords disabled, which greatly increases the difficulty of brute-force guessing attacks.
For more background and examples, see Detailed steps to create SSH key pairs.
For additional ways to generate and use SSH keys on a Windows computer, see How to use SSH keys with Windows on Azure.
Supported SSH key formats
Azure currently supports SSH protocol 2 (SSH-2) RSA public-private key pairs with a minimum length of 2048 bits. Other key formats such as ED25519 and ECDSA are not supported.
Create an SSH key pair
Use the
ssh-keygen
command to generate SSH public and private key files. By default, these files are created in the ~/.ssh directory. You can specify a different location, and an optional password (passphrase) to access the private key file. If an SSH key pair with the same name exists in the given location, those files are overwritten.The following command creates an SSH key pair using RSA encryption and a bit length of 4096:
If you use the Azure CLI to create your VM with the az vm create command, you can optionally generate SSH public and private key files using the
--generate-ssh-keys
option. The key files are stored in the ~/.ssh directory unless specified otherwise with the --ssh-dest-key-path
option. The --generate-ssh-keys
option will not overwrite existing key files, instead returning an error. In the following command, replace VMname and RGname with your own values:Provide an SSH public key when deploying a VM
To create a Linux VM that uses SSH keys for authentication, specify your SSH public key when creating the VM using the Azure portal, Azure CLI, Azure Resource Manager templates, or other methods:
If you're not familiar with the format of an SSH public key, you can display your public key with the following
cat
command, replacing ~/.ssh/id_rsa.pub
with the path and filename of your own public key file if needed:A typical public key value looks like this example:
If you copy and paste the contents of the public key file to use in the Azure portal or a Resource Manager template, make sure you don't copy any trailing whitespace. To copy a public key in macOS, you can pipe the public key file to
pbcopy
. Similarly in Linux, you can pipe the public key file to programs such as xclip
.The public key that you place on your Linux VM in Azure is by default stored in ~/.ssh/id_rsa.pub, unless you specified a different location when you created the key pair. To use the Azure CLI 2.0 to create your VM with an existing public key, specify the value and optionally the location of this public key using the az vm create command with the
--ssh-key-values
option. In the following command, replace VMname, RGname, and keyFile with your own values:If you want to use multiple SSH keys with your VM, you can enter them in a space-separated list, like this
--ssh-key-values sshkey-desktop.pub sshkey-laptop.pub
.SSH into your VM
With the public key deployed on your Azure VM, and the private key on your local system, SSH into your VM using the IP address or DNS name of your VM. In the following command, replace azureuser and myvm.westus.cloudapp.azure.com with the administrator user name and the fully qualified domain name (or IP address):
Mac Generate Ssh Key 4096
If you specified a passphrase when you created your key pair, enter that passphrase when prompted during the login process. The VM is added to your ~/.ssh/known_hosts file, and you won't be asked to connect again until either the public key on your Azure VM changes or the server name is removed from ~/.ssh/known_hosts.
If the VM is using the just-in-time access policy, you need to request access before you can connect to the VM. For more information about the just-in-time policy, see Manage virtual machine access using the just in time policy.
Next steps
- For more information on working with SSH key pairs, see Detailed steps to create and manage SSH key pairs.
- If you have difficulties with SSH connections to Azure VMs, see Troubleshoot SSH connections to an Azure Linux VM.
This tutorial will show you how to generate and secure SSH keys on macOS Sierra (10.12) and macOS High Sierra (10.13). SSH keys allow you to log into your server without a password. They increase convenience as well as security by being significantly more resistant to brute-force attacks.
SSH (Secure Shell) is a protocol most often used for remote management and for file transfer often denoted as sFTP (Secure File Transfer Protocol). When accessing a remote server such as a Vultr VPS, it is recommended to use SSH with PKE (Public Key Exchange) which uses a key-pair where the public key is provided to the server and the private key in stored on your machine.
SSH Keys can be automatically added to servers during the installation process by adding your public keys in the Vultr control panel. You can manage your SSH keys on this page. It is important to remember that these are your public keys only (usually denoted with
.pub
), you should never expose your private keys.Key types
There are several different key types that can be selected. Use the
-t
argument upon generation, such as ssh-keygen -t ed25519
. The ED25519 key type, which uses an elliptic-curve signature, is more secure and more performant than DSA or ECDSA. Most modern SSH software (such as OpenSSH since version 6.5) supports the ED25519 key type, but you may still find software that is incompatible, thus the default key type is still RSA.The default key type is 2048-bit RSA which offers good security and compatibility. For higher security, you can choose a larger key size using the
-b
argument on generation, such as ssh-keygen -b 4096
to create a 4096-bit RSA key pair.Key generation
To generate an SSH key, you will need to open
Terminal.app
found in 'Applications > Utilities > Terminal'.To create a 4096-bit RSA key pair, enter:
Then you will see:
Pressing Enter/Return will save your new key pair to this default location, which is recommended. You will then have the option to create a passphrase, which will encrypt the key so that it cannot be used without authorization. Using a passphrase is also recommended.
At this point, your keypair has been created and stored in
~/.ssh/id_rsa
. To make the key available to the system and store the passphrase in the system keychain, we will need to complete several additional steps. Note that this is only needed if you would rather not be prompted for the key passphrase each time it is used.Add new keypair to SSH agent
Mac Create Ssh Key 4096
Enter
ssh-add -K ~/.ssh/id_rsa
. You will then be prompted for the passphrase and you will see the following: If you would like to use this SSH key to log into a server that has already been created, you can use the
ssh-copy-id
tool to store the public key on the server you would like to access.Add new key to remote server
Using
ssh-copy-id
:The console will request your login password since the remote server is not yet aware of your key. You will see the following:
You can now attempt to log into the remote server with
ssh [email protected]
and you should be connected without a password prompt.