> ## Documentation Index
> Fetch the complete documentation index at: https://docs.palpabl.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Racks

> Model your data center infrastructure using Racks

# Racks

Racks are a common way to structurally organize network equipment and are typically key to understanding how a network works within a location.

The rack model represents either a two or four post equipment rack in which [devices](devices) can be installed. Each rack must be assigned to a [site](organization#site), and may optionally be assigned to a [location](organization#locations) within that site. Racks can also be organized by user-defined functional roles known as Rack Roles.

The name and facility ID of each rack within a location must be unique.

## Rack Height

Rack height is measured in rack units(U). Racks are commonly between 42U and 48U tall, Palpabl NMS allows you to define racks of arbitrary height. A toggle is provided to indicate whether rack units are in ascending (from the ground up) or descending order.

Each rack is assigned a name and (optionally) a seperate facility ID. This is designed to allow you to indicate what space in a data center has been leased for this rack, specifically in the event you have equipment in a data center you do not own.

## Reservations

Users can reserve specific units with a rack for future use. An arbitrary set of units within a rack can be associated with a single reservation, but reservations cannot span multiple racks. A description is required for each reservation, reservations may optionally be associated with a specific tenant.