Vertiv GL840ES-3042-B-MSS 44U Server Rack Enclosure with Split Mesh Rear Door
Overview
The Vertiv GL840ES-3042-B-MSS is a 44U open-frame-compatible server rack enclosure in a 30-inch-wide by 42-inch-deep black steel cabinet, configured with a split mesh rear door — the right starting point for mid-density compute and networking deployments where rear cable access and airflow management both matter. Part of the Vertiv rack enclosure line, the GL840ES-3042-B-MSS (often searched as GL840ES 3042 B MSS) ships in the black colorway and is sized to fit standard 19-inch rackmount equipment across its full 44U height.
The 30-inch width accommodates standard EIA-310 19-inch rackmount gear while leaving adequate side clearance for vertical cable managers and power distribution units. At 42 inches deep, this enclosure handles 1U switches, 2U servers, and deeper blade chassis without forcing awkward rear cable routing — a dimension that matters when you're mixing compute, storage, and networking in the same rack. If you're evaluating server rack enclosures for a new build-out or expansion, the 44U height delivers roughly 88U-equivalents of space when compared to a dual-rack 22U strategy, reducing floor footprint in dense deployments.
Key Features
- 44U Rack Height: 44U of usable vertical space handles full-height UPS units, deep storage arrays, top-of-rack switches, and patch panels in a single cabinet — fewer enclosures on the floor means fewer power distribution runs and simpler structured cabling paths.
- 30-Inch Cabinet Width: The 30-inch width is the common mid-tier footprint for data center enclosures — wider than the minimum 24-inch spec, which lets you mount vertical cable managers on both sides without sacrificing EIA-310 compliance or blocking air intake at the sides. If your floor tile grid runs on 24-inch or 30-inch centers, verify floor plan compatibility before ordering.
- 42-Inch Depth: At 42 inches, the cabinet accommodates most 1U–4U servers and deeper networking gear without overhang. Note that very deep blade chassis (some extend 36+ inches) will fit, but rear cable management space compresses — plan your power and data cabling routing accordingly.
- Split Mesh Rear Door: The split rear configuration divides the rear door into two independently swinging halves. In dense deployments this is a genuine workflow advantage: you can open one half to access cabling on one side without fully exposing the rear of the cabinet — useful in narrow hot-aisle/cold-aisle rows where swing clearance is limited. The mesh panels maintain rear airflow when closed, supporting front-to-rear cooling architectures common in enterprise compute environments.
- Mesh Contour Front Door Option: The front door uses a contoured mesh design, which allows conditioned cold aisle air to enter the cabinet without restriction. This matters in any deployment where your CRAC or in-row cooler delivers cold air to the front face — a solid door would create a pressure barrier and force airflow around rather than through the equipment.
- Black Colorway: The black finish is the standard datacenter and network closet color for rack enclosures — consistent with most major vendors' equipment aesthetics and standard in environments where visual uniformity across a row of racks is part of the build spec. Winter White is available in the GL840ES family for environments requiring it.
- Multiple Configuration Options in the GL840ES Family: The GL840ES enclosure family spans 24U through 52U heights, 24-inch through 32-inch widths, and 42-inch or 48-inch depths — so if this specific GL840ES-3042-B-MSS configuration doesn't match your floor plan or U-count requirement, a sibling SKU in the same family almost certainly does without changing your procurement relationship or accessory compatibility.
Integration and Compatibility
As part of the Vertiv GL840ES series, this enclosure is designed around standard EIA-310 19-inch rackmount compatibility. The family supports rack accessories including blanking panels, cable management rings, and toolless mounting hardware common across the Vertiv Geist rack line. Verify accessory compatibility by GL840ES family designation when ordering rails, shelf kits, or power distribution units — accessory rail spacing can differ between enclosure depth variants (42-inch vs. 48-inch) within the same series.
For structured cabling deployments, the 42-inch depth allows rear-mounted patch panels and cable managers to coexist with standard 1U–2U switching gear without conflicting with the split rear door swing radius. Coordinate with your structured cabling layout before finalizing the rear door clearance requirements for your specific aisle width.
Frequently Asked Questions
Q: What is the usable rack height of the GL840ES-3042-B-MSS?
A: The GL840ES-3042-B-MSS provides 44U of usable vertical rack space for standard 19-inch EIA-310 rackmount equipment.
Q: What door configuration does the GL840ES-3042-B-MSS ship with?
A: This specific SKU ships with a mesh contour front door and a split mesh rear door. The split rear door divides into two independently swinging halves, which aids cable access in tight aisle configurations while maintaining rear airflow when closed.
Q: What are the external dimensions of the GL840ES-3042-B-MSS?
A: The cabinet is 30 inches wide and 42 inches deep. Height corresponds to a 44U enclosure. Confirm exact external height in millimeters with the Vertiv GL840ES datasheet for floor-plan and raised-floor tile calculations.
Q: Does the GL840ES-3042-B-MSS come in colors other than black?
A: The GL840ES enclosure family is available in Black and Winter White. The GL840ES-3042-B-MSS specifically is the black variant. Consult the GL840ES family matrix for the Winter White equivalent SKU if required.
Q: Is the GL840ES-3042-B-MSS compatible with standard Vertiv Geist rack accessories?
A: The GL840ES series is designed to accept Vertiv Geist rack accessories including rails, blanking panels, and cable management hardware. Verify accessory part numbers against the GL840ES family (not just the GL840ES series broadly) to confirm fit, as depth variants (42-inch vs. 48-inch) may affect accessory rail compatibility.
Q: Are other U-height or depth options available in the same enclosure family?
A: Yes. The GL840ES family spans 24U, 42U, 44U, 48U, and 52U heights; 24-inch, 30-inch, and 32-inch widths; and 42-inch or 48-inch depths — giving a broad configuration matrix within the same product line.
The GL840ES-3042-B-MSS is a well-positioned 44U enclosure for the environments I see most often — mid-density enterprise compute rooms and network closets where the 30-inch-wide footprint fits the standard floor grid and the 42-inch depth handles everything from shallow patch panels to deeper 2U servers without drama. The split mesh rear door is the detail I'd call out to anyone sizing this cabinet for a narrow hot-aisle row: being able to swing one half independently without fully committing to an open rear is genuinely useful when working in a 36-inch aisle.
Technical Highlights:
- 44U Height: Full 44U of usable space gives you room to run a complete compute stack — top-of-rack switching, server rows, and a rear-mounted 1U KVM or console — without stacking a second enclosure or splitting a rack unit count across cabinets.
- Split Mesh Rear Door: Mesh panels maintain front-to-rear airflow compliance when closed; the split design cuts required aisle swing clearance roughly in half versus a single full-width rear door — a real consideration in 36-to-42-inch hot aisles.
- 30W × 42D Footprint: The 30-inch width clears the minimum 24-inch EIA spec while leaving room for vertical cable managers on both sides; 42-inch depth accommodates standard server chassis with comfortable rear cable management space behind the equipment.
Deployment Considerations:
- Verify raised-floor tile alignment before finalizing position — 30-inch-wide enclosures don't always land on standard 24-inch tile centers, which can affect floor cutout placement for power and data runs beneath the cabinet.
- The GL840ES family spans both 42-inch and 48-inch depth variants; if you're ordering accessories (rails, shelf kits, PDU arms) separately, confirm they're specified for the 42-inch depth version — some Vertiv Geist accessory kits are depth-specific and won't fit the deeper variant.
This enclosure fits squarely in the mid-density enterprise data center and large network closet space — the 44U height and split rear door make it a practical choice for IT integrators deploying structured compute and switching rows where aisle discipline and rear cable access are both operational priorities.
