Exam 3V0-21.21 All Questions

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Exam 3V0-21.21 topic 1 question 12 discussion

Actual exam question from VMware's 3V0-21.21

Question #: 12
Topic #: 1

An architect is designing a new vSphere environment with the following resources:
✑ 600 vCPU
✑ 5,760 GB RAM
Average resource usage is:
✑ 60 vCPU
✑ 1,152 GB RAM
The design must meet the following requirements:
✑ The environment has the ability to burst by 25%.
✑ Each host can schedule 36 vCPUs and has 512 GB RAM.
✑ Management overhead is 20%.
What is the minimum number of hosts required to meet the design requirements?

A. Three
B. Five
C. Four
D. Two

Show Suggested Answer

Suggested Answer: C 🗳️

by andy33 at April 6, 2021, 1:27 a.m.

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set10

Highly Voted 3 years, 6 months ago

I think it will be C (four hosts). Take for consideration "Management overhead is 20%." CPU: (60+60*0,25+60*0,2)/36 = ~ 2,4 (round up to 3) RAM: (1152+1152*0,25+1152*0,2)/512 = ~ 3,26 (round up to 4)

upvoted 20 times

primanturin

3 years, 6 months ago

C - 4 hosts CPU - (60+60*0.45)/36 = 2.4 RAM: (1152+1152*0.45)/512 = 3.2 Taking the higher number, therefore 3.2 > 4 hosts

upvoted 3 times

cloudsinair

3 years, 5 months ago

Kindly explain the math, 60+60 * 0.45 what is the reason for 60+60 and multiplied by .45?

upvoted 1 times

primanturin

3 years, 4 months ago

20/100=0.2 25/100= 0.25 Distributive property 60 + 60 *0.25 + 60*0.2 = 60 + 60(0.25+0.2) = 60 + 60*0.45

upvoted 2 times

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hansel

3 years, 6 months ago

In order to meet all 3 requirements im going with C A is not correct as its not factoring in the management overhead of 20%

upvoted 1 times

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FR_Wolfman

Most Recent 11 months, 4 weeks ago

Selected Answer: C

The resource needs are 60 vCPU and 1152GB RAM. With a 25% burst, we will need up to 75 vCPU (60x1,25), and 1440 GB RAM (1152x1,25). For that 3 hosts could be sufficient (108 vCPU, 1536 GB RAM). But, as we have to take in account a 20% Management overhead, we will need 94 vCPU (75/0,8) and 1800 GB RAM (1440/0,8)  so we need 4 hosts minimum to accommodate the necessary RAM.

upvoted 1 times

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Alchot

1 year, 10 months ago

Selected Answer: C

Take the worst metric as guidance = RAM Average usage ✑ 1,152 GB RAM The design must meet the following requirements: ✑ The environment has the ability to burst by 25%. X = Average usage ✑ 1,152 GB RAM + 25% for burst = 1440 ✑ Each host can schedule 36 vCPUs and has 512 GB RAM. ✑ Management overhead is 20%. Y = VM usage + Burst capacity = 1140 Z= 1140 + 20% = 1728 N Hosts = 1728 / 512GB RAM = 3.375 N Hosts > 3 Hosts

upvoted 3 times

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Uthitcomp

2 years, 3 months ago

can anyone provide a Link to explain how to calculate this equation?

upvoted 1 times

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VCIX

2 years, 4 months ago

C 4 HOSTS. Memory is the focus here. Vms use 1152gb ram + 25% burst = 1440gb + 20% mgmt = 1,728gb ram. Each host has 512gb ram so 4 hosts needed.

upvoted 3 times

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PSE_IT

2 years, 5 months ago

Selected Answer: C

CPU 60*1,25*1,2 = 90 /36 = 2,5 RAM 1152*1,25*1,2= 1728/512 = 3,37 Minimum can be 3 or 4 hosts. For best practices reasons i vote C (4 hosts).

upvoted 1 times

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guru2020

2 years, 9 months ago

Ans is 3 Avg vCPU usage = 60 Overhead - 20%, overhead for 60, = 60x20/100 = 12 Burst by 25%, Burst for 60=60x25/100=21 so, total vcpu utilization = 60+21+12 = 93 one host can give (schedule) 36 vCPU. So, how many host will provide 93 vCPU. 36 vCPUs given by hosts = 1 1 vCPUs given by hosts = 1/36 93 vCPUs given by hosts = (1/36)x93=2.58 let us round it to 3. So minimum 3 hosts are required. :)

upvoted 1 times

c11

2 years, 8 months ago

I think you didn't consider memory in your calculations. Do the same for RAM and your answer will be 4 hosts.

upvoted 1 times

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spam

2 years, 11 months ago

Selected Answer: C

Overhead will still be 20% even in burst. So 1152*1.25*1.20 would be more accurate. The worst situation. Whatever, C stay the answer.

upvoted 1 times

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Mezze

3 years, 4 months ago

Its 4 hosts for sure

upvoted 1 times

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arnor

3 years, 5 months ago

4 Hosts CPU = 60*1.25*1.2/36 = 2.5 (3 hosts) RAM = 3.375 (4 hosts) Management overhead costs from the total number of employed resources, both in the case of an average and in the case of a burst consumption

upvoted 1 times

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Achary

3 years, 7 months ago

Answer is C . 3 hosts

upvoted 2 times

nemisis95

3 years, 6 months ago

You mean A. 3 hosts

upvoted 2 times

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ennayaf

3 years, 7 months ago

Since question is asking for the minimum, I would go with Answer A = 3 host. CPU: (60 * 1.25)/36 = ~ 2.08 (round up to 3) RAM: (1152 * 1.25)/512 = ~ 2.81 (round up to 3) Take the higher of the 2 figures - in this case RAM at 2.81 hosts, round it up to get 3 host. However if the question did not ask for the minimum, the industry best practice is to size it at 100% capacity to use 4 host.

upvoted 3 times