feat(ins): add docs for ssh key tags

Author: bene2k1

compute/instances/reference-content/add-instance-specific-ssh-keys-using-tags.mdx

@@ -0,0 +1,105 @@
+---
+meta:
+  title: Using tags to add Instance-specific SSH keys
+  description: Find out how to use tags to add Instance-specific SSH keys.
+content:
+  h1: Using tags to add Instance-specific SSH keys
+  paragraph: Find out how to use tags to add Instance-specific SSH keys
+categories:
+  - compute
+dates:
+  validation: 2024-10-08
+tags: Instance ssh-key ssh tag
+---
+
+In cloud environments, managing SSH keys across multiple Instances is key to keeping your infrastructure secure and easy to access.
+Sometimes, you need to ensure that a specific SSH key grants access to only one Instance and doesn't automatically apply to others.
+This can simplify key management and improve security, especially when you're running many Instances
+
+
+<Macro id="requirements" />
+
+- A Scaleway account logged into the [console](https://console.scaleway.com)
+- [Owner](/identity-and-access-management/iam/concepts/#owner) status or [IAM permissions](/identity-and-access-management/iam/concepts/#permission) allowing you to perform actions in the intended Organization
+- An [SSH key](/identity-and-access-management/organizations-and-projects/how-to/create-ssh-key/)
+- An [Instance](/compute/Instances/how-to/create-an-Instance/)
+
+## The authorized_keys file
+
+Scaleway stores authorized SSH keys in the `/root/.ssh/authorized_keys` file. If you inspect this file, you might notice a small comment mentioning the use of tags to add SSH keys directly to Instances.
+
+```bash
+cat /root/.ssh/authorized_keys
+#
+# WARNING: Automatically generated file
+# This file will be erased at every boot
+# This file was generated with '/usr/sbin/scw-fetch-ssh-keys'
+#
+# To ad
+# To add a new key, you can:
+#   -- Add keys on your Scaleway account https://cloud.scaleway.com/#/credentials
+#   -- Add keys using server tags - https://cloud.scaleway.com/#/servers/<INSTANCE_ID>
+#        - i.e: "AUTHORIZED_KEY=ssh-rsa_XXXXXXXXXXX AUTHORIZED_KEY=ssh-rsa_YYYYYYYYYYYYYYY"
+#        - Be sure to replace all spaces with underscores
+#        - $> sed 's/ /_/g' ~/.ssh/id_rsa.pub
+#   -- Add the keys to '/root/.ssh/Instance_keys' which will be imported
+#
+# And recreate your 'authorized_keys' file with the new keys:
+#   -- Run 'scw-fetch-ssh-keys --upgrade'
+[...]
+```
+
+This file lists all the SSH public keys allowed to access the Instance. Our goal is to add an Instance-specific SSH key that will not be automatically applied to other Instances.
+
+
+## How to add Instance-specific SSH keys using tags
+
+1. Click **Instances** in the **Compute** section of the side menu. The [Instances overview](https://console.scaleway.com/Instance/servers) displays.
+2. Click the Instance you want to add a specific key to.
+3. Navigate to the section where you can add tags to the Instance on the Instances overview page.
+4. Add the public SSH key tag by writing in the **Tags** form. You can add multiple keys by creating separate `AUTHORIZED_KEY` tags for each SSH key.
+   The format for creating SSH key tags is:
+   ```bash
+   AUTHORIZED_KEY=ssh-rsa_XXXXXXXXXXX AUTHORIZED_KEY=ssh-rsa_YYYYYYYYYYYYYYY
+   ```
+   <Message type="important">
+   Remember to replace any spaces with underscores (`_`) in the SSH public key string when entering it as a tag. Your actual SSH public key remains unchanged.
+
+   For example, if your public key looks like this:
+   ```bash
+   ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIG1hT8oQksyU9BLjoTtI93xT9+Ds9YRHTUZXq99c2EC3
+   ```
+   In the tag field, you would enter:
+
+   ```bash
+   AUTHORIZED_KEY=ssh-ed25519_AAAAC3NzaC1lZDI1NTE5AAAAIG1hT8oQksyU9BLjoTtI93xT9+Ds9YRHTUZXq99c2EC3
+   ```
+   </Message>
+
+4. Once you have added the SSH key tag(s), they will be saved automatically in the Scaleway console.
+
+### Updating the keys on your Instance
+
+1. Run the following command:
+
+    ```bash
+    scw-fetch-ssh-keys --upgrade
+    ```
+2. Verify the SSH key on the Instance by typing
+
+    ```bash
+    cat /root/.ssh/authorized_keys
+    ```
+
+The Instance-specific key has been added to the /root/.ssh/authorized_keys file on the Instance alongside with your account-wide configured keys.
+The specific tag public key will not propagate to other Instances in your infrastructure.
+
+<Message type="tip">
+    Another option to update the SSH keys of your Instances is to reboot them.
+</Message>
+
+## Conclusion
+
+You now have configured an Instance-specific SSH key through the Scaleway console.
+One of the main advantages of using tags for SSH keys is that they will not apply to other Instances, even after updates or reboots.
+This ensures that only the designated Instance can be accessed with the specified SSH key.

menu/navigation.json

@@ -1353,6 +1353,10 @@
                     "label": "Configuring Instances manually on a Private Network",
                     "slug": "manual-configuration-private-ips"
                   },
+                  {
+                    "label": "Using tags to add Instance-specific SSH keys",
+                    "slug": "add-instance-specific-ssh-keys-using-tags"
+                  },
                   {
                     "label": "Compatibility between Scaleway OS Images and Flexible IPs",
                     "slug": "comaptibility-scw-os-images-flexible-ip"