Creating and connecting to your first Public Cloud instance

Find out how to get started with your Public Cloud service after the creation of a project

Last updated 26th January 2023


Considering best practices, OVHcloud Public Cloud instances require a different approach than a VPS or Dedicated server solution.

This guide will take you through the first steps of creating and connecting to a Public Cloud instance.



Step 1: Creating SSH keys

The SSH protocol ensures encrypted client-server communication. Using SSH keys further improves security by preventing any connections from a device that does not possess the matching key. Creating an SSH key set provides you with a public and a private key.

  • The public key will be added to your Public Cloud instance at installation.

  • The private key, stored on your client device, will then enable access to your instance without requiring the user password.

Please note that a key-based SSH login is mandatory for connections to Public Cloud instances with the exception of those running Windows operating systems. Public SSH keys added to your OVHcloud Control Panel will be available for Public Cloud services of all regions and data centres. You can only store RSA and ECDSA encrypted keys; ED25519 is currently not supported.

Login authentication on Windows instances requires only username and password.

Creating an SSH key using a Linux or Mac operating system

From a Mac computer or a device with a Linux OS installed, first open the command line application (Terminal). Verify that you have a ".ssh" folder in your $HOME directory. If the folder does not exist, create it:

$ mkdir ~/.ssh
$ chmod 700 ~/.ssh

Use the following command to create a 4096 bit RSA key:

$ ssh-keygen -b 4096

Using the "-t" option with this command allows you to specify a different encryption method, for example:

$ ssh-keygen -t ecdsa -a 256

The command will prompt you to save the newly created key in the standard file:

Generating public/private rsa key pair.
Enter file in which to save the key (/home/user/.ssh/id_rsa):

You can accept the default file by pressing "Enter". Now you will have the option to enter a passphrase to password-protect your SSH key. This is recommended for added security. Since only the corresponding private key will be required to access your Public Cloud instance from your working device, appropriate security measures should be applied at this point. The passphrase has to be entered when a connection to the instance is established.

Your SSH keys should be stored in the ".ssh" directory. The public key file will have ".pub" added to the filename.

Your identification has been saved in /home/user/.ssh/id_rsa.
Your public key has been saved in /home/user/.ssh/
The key fingerprint is:
SHA256:MRk+Y0zCOoOkferhkTvMpcMsYspj212lK7sEauNap user@hostname
The key's randomart image is:
+---[RSA 4096]----+
|     .. o        |
|    . .= o       |
|   o o  X        |
|. . . .          |
|. .=.o .S.       |
| =o.o.  .   .    |
|o +   .  . o ..  |
|.. .  .   oEoo . |
|o.        .o+oo  |

The private key should always be kept safe, and access to it strictly limited to authorised people only.

In order to view and export your public key, use the "cat" command on your ".pub" key file and copy the output:

$ cat ~/.ssh/
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC8teh2NJ42qYZV98gTNhumO1b6rMYIkAfRVazl

In a MacOS Terminal, you can also use the "pbcopy" and "pbpaste" commands to handle key strings. For example, use this command to copy the key from the file "" to the clipboard:

$ pbcopy < ~/.ssh/

Creating an SSH key using a Windows operating system

PuTTY is an open source SSH client software with a graphical user interface, available for Windows and other operating systems. You can use it to remotely connect to a Linux server. Its companion software, PuTTY Key Generator (PuTTYgen), can be used to create SSH keys.

First, download PuTTY from the official website, if it is not already installed. The recommended standard installation package includes PuTTYgen but it is available as a standalone file there as well. To find out if you have it available already, check your "programs" menu or use the Windows Search.

Open PuTTYgen and select a supported encryption algorithm. The example uses RSA. Enter 4096 as the number of bits, then click the Generate button.

generate key

Next, randomly move your mouse cursor about the area below the progress bar:

generated key

The key is ready when the progress bar is full.

save key

You can select and copy the public key from this window to save it in your OVHcloud Control Panel in Step 2.

Save both keys to files and use the option to enter a passphrase. Since only the corresponding private key will be required to access your Public Cloud instance from your working device, appropriate security measures should be applied at this point. The passphrase has to be entered when a connection to the instance is established.

Step 2: Storing public keys in the OVHcloud Control Panel

Regardless of the method that was used to create the SSH keys, you will now have a public key ready to be added to a Public Cloud instance. You can store public keys in the Public Cloud section of the OVHcloud Control Panel, in order to have them readily available when creating an instance.

Stored SSH keys are useful for a faster creation of your instances. To change key pairs and add users afterwards, please refer to the guide on Configuring additional SSH keys.

Log in to the OVHcloud Control Panel, go to the Public Cloud section and select the Public Cloud project concerned. Then, click on SSH Keys in the left-hand navigation bar under "Project Management".

Click on the Add an SSH key button. In the new window, enter a name for the key and paste your key string (copied in Step 1 from the public key file or the PuTTYgen window) into the "Key" field. Confirm by clicking Add.

add key

Step 3: Creating an instance

Log in to the OVHcloud Control Panel, go to the Public Cloud section and select the Public Cloud project concerned. On the "Home" page, click on Create an instance. (You can find the same functionality on the "Instances" page by clicking Instances in the left-hand navigation bar under "Compute".)

instance select

First, choose a server template according to your needs. The assistant will provide descriptions about the various use cases and server model availability. You can choose from these customised categories:

Server Type Guaranteed Resources Usage notes
General Purpose Development servers, web or business applications
CPU Video encoding or other high-performance computing
RAM Databases, analysis, and in-memory calculations
GPU Massively parallel processing power for specialised applications (rendering, big data, deep learning, etc.)
Sandbox - Hosted on shared resources for testing and development environments
Discovery - Hosted on shared resources for testing and development environments
IOPS Optimised for disk data transfer
Metal Dedicated resources with direct access to compute, storage and network resources

Your Public Cloud resources total will initially be limited for security reasons. You can verify quotas and request an increase in your OVHcloud Control Panel by clicking Quota and Regions in the left-hand navigation bar under "Project Management".

Note that you can upgrade your instance later but you will not be able to switch to a smaller model, unless you choose the "Flex" option in step 4 of the creation. Please see below for more details on this.

In the next step, choose a data centre for your Public Cloud instance.

The third option is where you select an operating system for the instance. Which images are available in this step depends on the choices made in previous steps, i.e. compatibility with the server type and the region. Operating systems with pre-installed applications are also available.

image select

If you select an operating system that requires paid licensing, these costs will automatically be included in the monthly or hourly billing.

This step also requires an SSH key to be added (Windows instances excluded), either by pasting the key directly via Add a key or selecting it from the list, provided you have stored it in the Control Panel in Step 2.

key select

The fourth step allows to configure some additional options.

options select

  • You can deploy multiple instances with the chosen setup (within your initial quota mentioned above).
  • You can choose to create a flexible instance which allows you to later downgrade to a smaller model (even switching server model categories) but it will limit the instance to 50GB of included storage at all times, regardless of upgrades or downgrades.
  • You can change the display name for your instance.
  • You can add a post-installation script.
  • You can enable automatic backups for the instance(s). Please take note of the pricing information and the rotation option details.

When you have applied your choices, click on Next to configure your network.

configure network

Depending on how you intend to use your instances, you can select the Public mode or Private mode.

The Public mode is the standard network model, it allows your instances to have a public network port attached. Associated with the vrack, each instance has a public and a private IP.

The Private mode provides you with the possiblity of assiging your instances to a private network only. Instances in this mode can only be exposed to the public network using a Gateway or a Loadbalancer service with Floating IPs. For more information, please consult our Public Cloud Network Services guides.

Once you have selected a mode, select a private network to attach your instance to or click on Create a new private network to create a new one.

When you have applied your choices, click Next to proceed to the final step and decide on a billing method.

billing select

We recommend to choose hourly billing if there is any doubt regarding the usage period, because it is not possible to choose it after the service delivery. You will have the option to switch to a monthly subscription as soon as the instance is available on the "Instances" page.

If you choose to be billed hourly, you will continue to be billed as long as the instance is not deleted. It does not matter if the instance is not actually used during this time.

Once you have made sure that your configuration choices are correct, click on the Create an instance button to finish creating your new instance. It may take a few minutes until your service is delivered.

Step 4: Connecting to your instance

Log in to the OVHcloud Control Panel, go to the Public Cloud section and select the Public Cloud project concerned. Then, click on Instances in the left-hand navigation bar under "Compute". Your instance is ready when the "Status" column in the table is set to "Activated". To verify, you can click on the "Refresh" button right next to Create an instance.

instances page

A user with elevated permissions is automatically created on the instance. The username reflects the chosen image, e.g "ubuntu", "debian", "fedora", "arch" etc. You can verify this, as well as all other specifications on the instance's "Dashboard" by clicking on ... and then on Instance details.

If you encounter issues with your connection, i.e. errors regarding your SSH keys, please refer to the guide on Replacing your lost SSH key pair.

If you have created an instance without an SSH key, via the OVHcloud API or the OpenStack Horizon interface, you can only add an SSH key to your instance via rescue mode by following the instructions set out in this section of the appropriate guide.

Connecting to a Linux OS instance from Linux OS / Mac

You can now access your instance through a command line interface (Terminal) via SSH. Replace "username" in the following examples with your default user as explained above. You can also simply copy the complete login command from the OVHcloud Control Panel by clicking on it in the instance's "Dashboard" and then paste it into your Terminal.

instances page

Type the passphrase for your private key when prompted.

ssh username@IPv4_of_your_instance
Enter passphrase for key '/Users/username/.ssh/id_rsa':

Since you are logged in with root privileges ("sudo user"), you can immediately enter commands to perform administrative tasks. It is advisable to first change your password:

$ sudo passwd username
New password:
Retype new password:
passwd: password updated successfully

You can now use these credentials to log in via the VNC console in your OVHcloud Control Panel. Next, switch to the "root" user and set a secure password, then switch back to the previous user:

$ sudo su -
# passwd
New password:
Retype new password:
passwd: password updated successfully
# su - username

Note that switching to the "root" user is rarely necessary; as a best practice for administration tasks that require root privileges, log in and execute commands as a user who is included in the "sudo" group.

Connecting to a Linux OS instance from Windows

After creating and saving your SSH keys (in Step 1) and installing your instance with the public key (in Step 3), you can use PuTTY and your private key to connect to your instance.

Open PuTTY and expand "SSH" in the left-hand menu, then click on "Auth" to see the authentication options.

using putty

Click the Browse button to navigate to the folder where your private key file (.ppk) is located and open it. Next, switch to "Session" via the left-hand menu and enter your login credentials (username@IPv4_address). Replace "ubuntu" in the example screenshots with your appropriate default user according to the instance's "Dashboard" in your OVHcloud Control Panel. (Click on Instances in the left-hand navigation bar, then click on the instance's name.)

For future connections, you can now save this session to have it available from the list in this interface. Enter a descriptive name under "Saved Sessions" and click on Save to add it.

using putty

Next, click on Open and you will be prompted to enter the key's passphrase.

using putty

The instructions above describe a best practice approach to connect to your Public Cloud instances in a secure manner. For convenience and security purposes, consider to also use a password manager on your device, such as the free and open source solution KeePass.

Connecting to a Windows OS instance

After the instance has been created, the Windows installation needs to be finalised (sysprep). To achieve this, click on ... and then on Instance details. Switch to the tab VNC console. The console should already display the post-installation interface.

windows sysprep

In the first step, decide on your localisation settings by selecting a region, a language and a keyboard layout. Click on Next to proceed.

windows sysprep

The second step requires to set up the default "Administrator" account. Enter your passphrase twice and click on Finish to complete the installation process. Use the eye symbol to check if all the characters entered into the fields match the actual layout of your keyboard.

The instance will reboot and you will be able to log in with these credentials using a remote desktop client.

From Windows

Use the Windows Search if necessary and open the native "Remote Desktop Connection" client application.

windows remote

Enter the IPv4 address of your instance and "Administrator" as the user, then type your passphrase. Usually, a warning message will appear, asking to confirm the connection because of an unknown certificate. Click on Yes to log in to the instance.

If you experience any issues with this procedure, verify that remote (RDP) connections are allowed on your device by checking your system settings, firewall rules and possible network restrictions.

From a Linux OS

Public Cloud instances can be accessed via the built-in VNC console in the OVHcloud Control Panel. From your local device, connections must be established by a client application that is capable of the Remote Desktop Protocol (RDP).

For example, Remmina Remote Desktop Client is a compatible application which should be included in an Ubuntu Desktop installation. If you do not find Remmina in your environment, you can obtain it from the official website.

linux remote

Open Remmina and make sure the connection protocol is set to "RDP". Enter the IPv4 address of your Public Cloud instance and press "Enter".

linux remote

If a certificate message appears, click on Yes. Next, enter username and password for the instance and click on OK to establish the connection.

linux remote

Go further

Backing up an instance

Increasing Public Cloud quota

Switching from hourly to monthly billing

Configuring additional SSH keys

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