Exam 3V0-624 topic 1 question 25 discussion

A) Matching vCPU with the physical CPU cores provide best performance. However, we don't know how many VMs are required, therefore there's a risk of a high CPU overcommitment (especially in case of failover), which will impact on performance. Also, if the application doesn't need/use 8 cores, their use will be scheduled anyway therefore wasting resources (we don't know that, but if 1 vCPU is enough for the application then it would be counterproductive to configure it with 8) B) It'd be good practice to start a VM with lower vCPU possible and then increase if needed. This solution lower the risk of over-commitment, and guest clustering is supported for HA. This provides both guest and hardware failover. Might or might not have lower performance, requirements of the application (and host network/storage specifications) are not mentioned. C) No, FT supports up to 4 vCPU d) No, FT doesn't support OS (Microsoft at least) failover clustering: https://docs.vmware.com/en/VMware-vSphere/6.5/vsphere-esxi-vcenter-server-651-setup-mscs.pdf p.13 A bit tricky not knowing more details about application and OS, but I'd say B (assuming HW supports it), as it provides failover for both OS and HW failures and won't cause high CPU overcommitment (hence answering all 3 questions).

B is the right one: - guest level clustering + vSphere HA provides all the best result for 3 requirements - can be scaled both up and out later when resource requirements will be clear

correct answer:B

I would have to say "D" as there is no mention of shared storage therefore vSphere HA is out. The question says "VM sizing strategy...highest level of uptime, individual VM performance, and failover capacity" - all that can only be achieved with option "D". "A" won't work as there is no shared storage. "B" can work but it doesn't provide the "highest level of uptime". "C" is not possible with the exam version of vSphere 6.5 U1.

In addition to the FT limitation (4/8 vCPU per VM and 8 vCPU per host), there is a statement on Course "VMware vSphere - Design Workshop" , Module 8 - Virtual Machine Design: Rightsize your VMs: Start with minimum guest resource requirements, then increase resources to improve application performance: • Use vRealize Operations Manager to help you rightsize your VMs and make efficient use of host resource capacity • Where possible, decrease resources to reduce wasted capacity.

B is the right answer

Reading the question my first answer was B. VCAPito also has a very good explanation which was my also close to my thought process while reviewing the question.

Answer is C (if VCAP 6.5 considers maximum and minimum of vSphere 6.5) For vSphere 6.5 the maximum of vCPU per VM for FT is 4vCPU, maximum 8vCPU protected on a host and only 4 VMs protected. While in vSphere 6.5 U1 and 6.7 it supports up to 8vCPU per VM, but the same 8vCPU protected on a host and the same 4 VMs protected. It makes no sense to have an OS cluster that offers high availability and spend twice as many resources to protect them with FT in a 3 ESXi cluster with 8 cores. Since it is enough to protect them with HA. Considering that the statement says the highest level of Uptime and Individual Performance then this covers it with FT and 8vCPU per VM. This way you could protect: A single VM per host (in vSphere 6.5U1 or higher) located on host1, the secondary copy would be on the other host2 and host3 would remain for high availability. For this reason, the answer is C (Assuming that VCAP 6.5 also takes into account the maximum values ​​of 6.5 U1). If, on the other hand, it only takes into account only the maximum values ​​of vSphere 6.5 U1 then the Answer would be D, since it could NOT protect 8vCPU (but if 4 VM of 1 vCPU), and the highest level of Uptime would achieve it with OS Level cluster and FT.