Creating and configuring a security group in Horizon

Find out how to create a security group and configure it on a Public Cloud instance

Last updated 24th August 2021


For security reasons, you can configure and use filtering rules that will define access to your instances. You can allow or block certain incoming or outgoing connections using security groups. These rules can be applied for traffic from certain IP addresses, or even for instances configured on particular security groups.

Find out how to create a security group, and configure it on a Public Cloud instance.



Step 1: creating a security group

Access the Horizon interface. Then choose the region in which you want to create a security group, via the button in the top left-hand corner.

define region

If a security group is to be used in several regions, you must create it for each region.

Now expand the Network menu and click Security Groups. A table lists the security groups created. The default group is already listed here. This will allow all incoming and outgoing traffic to pass through.

To add a new security group, click the + Create Security Group button.

access security groups

On the page that appears, give a name and description to the group you are about to create. Once you have done this, click the Create Security Group button.

create security group

Returning to the Security Groups tab, the table now displays the newly created group. Rules are configured by default. These allow only outgoing traffic to pass.

If you would like to modify these, go to the next step.

If you are satisfied with these rules, go to Step 3: Configure a security group on your instance.

Step 2: configuring security group rules

To change the default rules, or if your needs change, click the Manage Rules button.

manage rules

If you have left the default rules on your security group, they will only let outgoing traffic pass through.

root@server:~$ ssh

ssh connect to host port 22: Connection timed out

On the rules management page, you can:

  • delete an existing rule: Use the Delete Rule button.
  • add a new rule: use the + Add Rule button.

When you add a rule, you will need to fill in the information requested, then click Add.

In our example, we will authorise the SSH connection to the instance.

add a rule

Once you have added the new rule, wait a few minutes for it to take effect.

root@server:~$ ssh

Last login: Tue Oct 13 13:56:30 2015 from

Configuring a security group on an instance

From the Horizon interface, expand the Compute menu and select Instances. From this page, create a new instance via the Launch Instance button.

When you create your instance, you can choose the new security group created in the previous step via the Security Groups menu.

assign security group

You can apply a new security group to an instance that has already been created by clicking Edit Security Groups to the right of the instance.

edit security group

Deleting a security group

To delete a security group, select it by ticking the corresponding box on the left, then click Delete Security Groups.

delete security group

Go further

Join our community of users on

Did you find this guide useful?

Please feel free to give any suggestions in order to improve this documentation.

Whether your feedback is about images, content, or structure, please share it, so that we can improve it together.

Your support requests will not be processed via this form. To do this, please use the "Create a ticket" form.

Thank you. Your feedback has been received.

These guides might also interest you...

OVHcloud Community

Access your community space. Ask questions, search for information, post content, and interact with other OVHcloud Community members.

Discuss with the OVHcloud community