Server Room Sizing (Based on TIA-942)

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Type 1: Based on the Growth in the Number of Racks

Objective:

Rule 1: The value of the Extended Factor is based on the trend (slope) of IT equipment development over the past five years, and this trend is used to predict development for the next five years.

Therefore, linear regression is used to determine the slope and intercept of this line.

Python Code:

We calculate the slope of the trend line:

from sklearn.linear_model import LinearRegression
import numpy as np

# Your data
x = [90, 91, 92, 93, 94]
y = [3, 5, 6, 8, 8]

# Convert x to 2D array
X = np.array(x).reshape(-1, 1)
Y = np.array(y)

# Create and fit the model
model = LinearRegression()
model.fit(X, Y)

# Get slope and intercept
slope = model.coef_[0]
intercept = model.intercept_

print("Slope:", slope)
print("Intercept:", intercept)

Output:

Slope: 1.3
Intercept: -113.60000000000001

Conclusion:

This gives us a linear growth function:

y=1.3x113.6y=1.3x-113.6

For x = 99, which is the 5-year projection:

y=(1.3×90)113.6=15.1Number  of  racks=16y=(1.3\times 90)-113.6=15.1 \Rightarrow Number\;of\;racks=16

Type 2: Based on the Growth in the Number of Active Devices

Suppose you have data on the number of active equipment in a data center over several years:

Year
Equipment Count

90

238

91

241

92

243

93

245

94

246

You want to predict the number of active equipment in year 99 based on this data using linear regression.

Step 1: Prepare the data

We first collect our years and equipment counts as lists:

years = [90, 91, 92, 93, 94]
equipment_counts = [238, 241, 243, 245, 246]

Step 2: Import necessary libraries and prepare data for modeling

We'll use scikit-learn, a powerful Python library for machine learning:

from sklearn.linear_model import LinearRegression
import numpy as np

# Convert years to a 2D array as required by scikit-learn
X = np.array(years).reshape(-1, 1)
y = np.array(equipment_counts)

Step 3: Create and train the linear regression model

model = LinearRegression()
model.fit(X, y)

Step 4: Extract the slope and intercept

These tell us the equation of the best-fit line:

y=mx+by=mx+b
slope = model.coef_[0]
intercept = model.intercept_

print("Slope:", slope)
print("Intercept:", intercept)

Step 5: Predict equipment count for year 99

year_to_predict = 99
predicted_count = model.predict([[year_to_predict]])
print(f"Predicted equipment count in year {year_to_predict}: {predicted_count[0]:.2f}")

Output

Slope: 2.0000000000000004
Intercept: 60.599999999999966
Predicted equipment count in year 99: 258.60

What is a Networking Rack?

A networking rack (also known as a server rack or equipment rack) is a metal frame used to mount IT equipment like:

  • Network switches

  • Routers

  • Patch panels

  • Servers

  • UPS units

Racks help keep everything organized, cool, and easily maintainable, especially in data centers or communication rooms.

What is a "U" (Rack Unit)?

The height of equipment that fits into a rack is standardized using rack units, abbreviated as "U".

  • 1U = 1.75 inches (44.45 mm) in height.

  • Equipment is usually labeled as 1U, 2U, 4U, etc., based on how many units tall it is.

Example:

  • A 42U rack can hold up to 42U of equipment.

    • That could be 42×1U devices or 21×2U devices, etc.

What is Rack Depth?

Rack depth refers to the distance from the front to the back of the rack. This is important because some equipment is deeper (longer) than others.

Common rack depths:

  • 600 mm (shallow) – for basic networking gear.

  • 800 mm to 1000 mm (standard) – fits most servers and switches.

  • 1200 mm (deep) – used for full-size enterprise servers or large UPS units.

Always make sure the depth of your rack is compatible with your devices.

Rack Layout Planning

Given

  • 1 Rack = 42U42U

  • Active Equipment = 260U260U

In calculations related to infrastructure planning (e.g., rack space, cooling, or power estimation), it's common to estimate the amount of passive equipment as a percentage of active equipment.

Rule 2: In our calculations, the amount of passive equipment is considered to be 30% of the total active equipment.

So, the total estimated U is equal:

Total=260×1.3=338Total=260\times 1.3=338

To determine how many racks are required to accommodate 338U:

Number  of  racks=338428Number\;of\;racks=\frac{338}{42}\simeq 8

So, at least 8 racks are required.

Rule 3: The distance between the racks and between the racks and the wall must be at least one meter.

Rule 4: To accommodate support equipment such as cooling systems and UPS, an oversize equivalent of 40% is considered in the calculations. (at least 20%)

WidthFinal=4.4×1.4=6.16m    and    Lengthfinal=5.2×1.4=7.28mWidth_{Final}=4.4\times 1.4=6.16m\;\;and\;\;Length_{final}=5.2\times 1.4=7.28m

Minimum Server Room Height

Component
Height (cm)

Under raised floor

30

Equipment height (rack space)

205

Cable tray above racks

46

Clearance above ceiling

20

Hence:

Total=30+205+46+20=301(cm)=3.01(m)Total=30+205+46+20=301(cm)=3.01(m)

Final Summary of Room Sizing

Parameter
Value

Number of Racks

8

Required Units

325U

Room Width (X)

6.16 m

Room Length (Y)

7.28 m

Internal Height

3.01 m

Oversizing Applied

Yes (40%)

Layout Type

Hot/Cold Aisle

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