Multiple deploy keys

content/developers/overview/managing-deploy-keys.md

@@ -83,6 +83,32 @@ See [our guide on Git automation with tokens][git-automation].
 7. Select **Allow write access** if you want this key to have write access to the repository. A deploy key with write access lets a deployment push to the repository.
 8. Click **Add key**.
 
+##### Using multiple repositories on one server
+
+If you use multiple repositories on one server, you will need to generate a dedicated key pair for each one. You can't reuse a deploy key for multiple repositories.
+
+In the server's SSH configuration file (usually `~/.ssh/config`), add an alias entry for each repository. For example:
+
+```bash
+Host {% if currentVersion == "free-pro-team@latest" %}github.com{% else %}my-GHE-hostname.com{% endif %}-repo-0
+        Hostname {% if currentVersion == "free-pro-team@latest" %}github.com{% else %}my-GHE-hostname.com{% endif %}
+        IdentityFile=/home/user/.ssh/repo-0_deploy_key
+
+Host {% if currentVersion == "free-pro-team@latest" %}github.com{% else %}my-GHE-hostname.com{% endif %}-repo-1
+        Hostname {% if currentVersion == "free-pro-team@latest" %}github.com{% else %}my-GHE-hostname.com{% endif %}
+        IdentityFile=/home/user/.ssh/repo-1_deploy_key
+```
+
+* `Host {% if currentVersion == "free-pro-team@latest" %}github.com{% else %}my-GHE-hostname.com{% endif %}-repo-0` - The repository's alias.
+* `Hostname {% if currentVersion == "free-pro-team@latest" %}github.com{% else %}my-GHE-hostname.com{% endif %}` - Configures the hostname to use with the alias.
+* `IdentityFile=/home/user/.ssh/repo-0_deploy_key` - Assigns a private key to the alias.
+
+With these entries added, you can then use the alias of the hostname to interact with the repository using SSH, so the unique deploy key for that alias used. For example:
+
+```bash
+$ git clone git@{% if currentVersion == "free-pro-team@latest" %}github.com{% else %}my-GHE-hostname.com{% endif %}-repo-1:OWNER/repo-1.git
+```
+
 ### Machine users
 
 If your server needs to access multiple repositories, you can create a new {% data variables.product.product_name %} account and attach an SSH key that will be used exclusively for automation. Since this {% data variables.product.product_name %} account won't be used by a human, it's called a _machine user_. You can add the machine user as a [collaborator][collaborator] on a personal repository (granting read and write access), as an [outside collaborator][outside-collaborator] on an organization repository (granting read, write, or admin access), or to a [team][team] with access to the repositories it needs to automate (granting the permissions of the team).