Generate Your Private/Public Key-pair $ ssh-keygen -t rsa -C '[email protected]' By default your private key will be stored in /.ssh/idrsa: This is your private key and it must be kept secret /.ssh/idrsa.pub: This is your public key, you can share it (for example) with servers as an authorized key for your account. You can change the location.
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
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.
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.
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:
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
.
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):
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.
Steam. 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.
You generate an SSH key through macOS by using the Terminal application. Once you upload a valid public SSH key, the Triton Compute Service uses SmartLogin to copy the public key to any new SmartMachine you provision.
Joyent recommends RSA keys because the node-manta CLI programs work with RSA keys both locally and with the ssh agent. DSA keys will work only if the private key is on the same system as the CLI, and not password-protected.
Terminal is the terminal emulator which provides a text-based command line interface to the Unix shell of macOS.
To open the macOS Terminal, follow these steps:
The Terminal window opens with the commandline prompt displaying the name of your machine and your username.
An SSH key consists of a pair of files. One is the private key, which should never be shared with anyone. The other is the public key. The other file is a public key which allows you to log into the containers and VMs you provision. When you generate the keys, you will use ssh-keygen
to store the keys in a safe location so you can bypass the login prompt when connecting to your instances.
To generate SSH keys in macOS, follow these steps:
Enter the following command in the Terminal window.
This starts the key generation process. When you execute this command, the ssh-keygen
utility prompts you to indicate where to store the key.
Press the ENTER key to accept the default location. The ssh-keygen
utility prompts you for a passphrase.
You will need to enter the passphrase a second time to continue.
After you confirm the passphrase, the system generates the key pair.
Your private key is saved to the id_rsa
file in the .ssh
directory and is used to verify the public key you use belongs to the same Triton Compute Service account.
Never share your private key with anyone! |
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Your public key is saved to the id_rsa.pub
;file and is the key you upload to your Triton Compute Service account. You can save this key to the clipboard by running this:
Now you must import the copied SSH key to the portal.
You may see a password prompt like this:
This is because:
id_rsa
) does not match the public key stored with your Triton Compute Service account.Right in the portal, you can easily create Docker containers, infrastructure containers, and hardware virtual machines.
In order to use the Terminal to create instances, set up triton
and CloudAPI as well as the triton-docker
commandline tool.