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docs/customization/custom-links.md

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+# Custom Links
+
+Custom links allow users to display arbitrary hyperlinks to external content within NetBox object views. These are helpful for cross-referencing related records in systems outside NetBox. For example, you might create a custom link on the device view which links to the current device in a network monitoring system.
+
+Custom links are created by navigating to Customization > Custom Links. Each link is associated with a particular NetBox object type (site, device, prefix, etc.) and will be displayed on relevant views. Each link is assigned text and a URL, both of which support Jinja2 templating. The text and URL are rendered with the context variable `obj` representing the current object.
+
+For example, you might define a link like this:
+
+* Text: `View NMS`
+* URL: `https://nms.example.com/nodes/?name={{ obj.name }}`
+
+When viewing a device named Router4, this link would render as:
+
+```no-highlight
+<a href="https://nms.example.com/nodes/?name=Router4">View NMS</a>
+```
+
+Custom links appear as buttons in the top right corner of the page. Numeric weighting can be used to influence the ordering of links.
+
+## Context Data
+
+The following context data is available within the template when rendering a custom link's text or URL.
+
+| Variable | Description |
+|----------|-------------|
+| `obj`      | The NetBox object being displayed |
+| `debug`    | A boolean indicating whether debugging is enabled |
+| `request`  | The current WSGI request |
+| `user`     | The current user (if authenticated) |
+| `perms`    | The [permissions](https://docs.djangoproject.com/en/stable/topics/auth/default/#permissions) assigned to the user |
+
+## Conditional Rendering
+
+Only links which render with non-empty text are included on the page. You can employ conditional Jinja2 logic to control the conditions under which a link gets rendered.
+
+For example, if you only want to display a link for active devices, you could set the link text to
+
+```jinja2
+{% if obj.status == 'active' %}View NMS{% endif %}
+```
+
+The link will not appear when viewing a device with any status other than "active."
+
+As another example, if you wanted to show only devices belonging to a certain manufacturer, you could do something like this:
+
+```jinja2
+{% if obj.device_type.manufacturer.name == 'Cisco' %}View NMS{% endif %}
+```
+
+The link will only appear when viewing a device with a manufacturer name of "Cisco."
+
+## Link Groups
+
+Group names can be specified to organize links into groups. Links with the same group name will render as a dropdown menu beneath a single button bearing the name of the group.