2-post vs. 4-post racks: Pros and cons

March 13, 2019
Think you’re ready to pick out a rack for your IT equipment? You might not be if you don’t understand the different products on the market.

By the BLACK BOX TECHNOLOGY BLOG -- Think you’re ready to pick out a rack for your IT equipment? You might not be if you don’t understand the different products on the market. To help you make an informed decision, we wrote this blog that details the difference between 2-post racks and 4-post racks. As a bonus, we will discuss wallmount frames and brackets and their benefits. Let’s start by explaining 2-post racks.

Freestanding 2-Post Racks

Freestanding 2-post racks are also known as telco racks or relay racks. They are commonly used to mount light IT equipment, such as punch down panels and switches. These racks have a frame with two vertical upright rails equipped with M6 or tapped rail holes to mount equipment. Most users bolt them to the floor to increase stability. Below are the reasons end users choose 2-post racks:

Top Benefits of 2-Post Racks
  • Perfect solution for mounting patch panels, hubs, shelves and more
  • Great for secure computer rooms where access is restricted and locking cabinets aren’t needed
  • Made of rugged, economical steel to ensure reliability
  • Super-easy to assemble and disassemble
  • Affordability: A 2-post rack can be half the cost of a typical 4-post rack
  • Every Black Box 2-post rack supports standard 19-inch TIA/EIA mounting and features tapped holes for mounting equipment

Product Focus: Racks and Enclosures

Freestanding 4-Post Racks

So how does a 4-post rack differ from a 2-post rack? Besides the obvious difference in the number of posts, 4-post racks are made to carry heavier IT equipment, such as full servers, large routers and switches. They feature a frame with four vertical upright rails, often with adjustable depth to work with a variety of IT equipment. Here are the main reasons end users choose 4-post racks:

Top Benefits of 4-Post Racks
  • Solid aluminum or steel construction with four vertical upright rails
  • Can hold up to 19-inch servers, panels, routers, large switches and other components
  • Four stable beams provide better protection for equipment
  • Better cable management with secure runs that prevent damaged cables and outages
  • Adjustable depth up to 41 inches
  • Weight capacity up to 2400 pounds (1100 kilograms)
  • Ships unassembled with all mounting hardware included for safe and cost-efficient transport
  • EIA 310-D compliant


Now that you have a good understanding of 2-post and 4-post racks, we are going to detail some other useful tools for storing IT equipment: wallmount frames and brackets.

Wallmount Frames and Brackets

Wallmount frames and brackets are used in smaller installations where network equipment (small switches, access points or patch panels) needs to be stored. They are also often found on test benches for temporary installation. And, as expected, here’s a list of their other benefits:

Top Benefits of Wallmount Frames and Brackets
  • Ideal for installing patch panels
  • Feature universal left- or right-hinging design for easy handling
  • TIA/EIA spacing allows for easy mounting in 2U, 3U or 4U

But that’s not all. Wallmount frames up to 25RU can hold 19-inch equipment that weighs 75 pounds (34 kilograms). They provide an extremely stable design with four steel-made uprights. They also boast quick-release pins that allow the rack to swing open easily and give simple rear access for punching down cable or troubleshooting any issues you may have.

A variation of typical wallmount brackets are flushmount wall brackets. These brackets are the best option for installations with limited space, as they allow you to vertically mount equipment against a wall. They offer tapped rail holes to accommodate 19-inch equipment in 3U or 6U high rack space.

Which Rack Is Right for You?

You need to consider the space in your data center, the amount and type of IT equipment you want to store, your budget and future storage requirements before purchasing a rack. Browse the entire line of Black Box wallmount racks.

Black Box eyes growth of intelligent digital edge, launches 8 new websites to serve enterprises globally

Sponsored Recommendations

400G in the Data Center

Aug. 3, 2022
WHATS NEXT FOR THE DATA CENTER: 400G and Beyond

Power up your system integration with Pulse Power - the game-changing power delivery system

May 10, 2023
Pulse Power is a novel power delivery system that allows System Integrators to safely provide significant power, over long distances, to remote equipment. It is a Class 4 power...

The Agile and Efficient Digital Building

May 9, 2023
This ebook explores how intelligent building solutions can help businesses improve network infrastructure management and optimize data center operations in enterprise buildings...

Revolutionize Your Network with Propel Fiber Modules

Oct. 24, 2023
Propel Fiber Modules are your gateway to the future of connectivity.