What Is Live Migration in Cloud Computing?
A company hosts a critical web application on a virtual machine (VM) in a public cloud. The IT team needs to move the VM to a new physical host in the same datacenter to free up resources on the current host. The application must remain accessible via its existing private IP address, and downtime must be minimized. Which cloud feature BEST meets these requirements?
Quick Answer
The answer is live migration, the cloud feature that moves a running virtual machine between physical hosts with zero downtime and no change to its network identity. This works by transferring the VM’s memory and state incrementally while the application continues to run, then briefly pausing to finalize the switch, so the existing private IP address remains active and the service stays accessible. On the CompTIA A+ Core 1 220-1101 exam, this concept tests your understanding of high-availability and resource optimization in cloud environments—often appearing in scenario-based questions where uptime and IP persistence are critical. A common trap is confusing live migration with cold migration (which requires a shutdown) or with load balancing (which distributes traffic but doesn’t move the VM itself). Remember the mnemonic “Live means leave IP, vanish downtime” to recall that live migration preserves the IP address and eliminates visible disruption.
⚠ Common exam trap
Test-takers frequently confuse 'Elastic IP' with the ability to preserve an IP address during migration, but Elastic IP only applies to public IPs and does not handle the underlying VM relocation or private IP continuity.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Live migration
Live migration (also known as vMotion in VMware environments) allows a running virtual machine to be moved from one physical host to another with no downtime and without changing its network identity, including the private IP address. This meets the requirement to free up resources on the current host while keeping the application accessible via its existing IP and minimizing disruption.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Live migration
Why this is correct
Live migration moves a running VM between physical hosts while preserving its memory and network state, so the existing private IP address is retained and the application stays reachable. This satisfies both constraints: IP preservation and minimal downtime, unlike stop-start relocation which interrupts service.
- ✗
Elastic IP
Why it's wrong here
An Elastic IP is a public, internet-routable address, so it cannot preserve the VM's existing private IP when the instance moves hosts. It is tempting because Elastic IPs are reassociated between instances to mask host changes, which is correct when clients connect over the public internet rather than a private address.
- ✗
Virtual private cloud (VPC)
Why it's wrong here
A VPC is a network boundary, not a migration mechanism; it cannot relocate a running VM between physical hosts or preserve its private IP during that move. It is tempting because VPCs isolate and segment cloud resources, and would be the right choice when designing subnets, routing and security boundaries for a new deployment.
- ✗
Reserved instance
Why it's wrong here
A reserved instance is a billing commitment for capacity, not a live migration feature, so it neither moves the VM nor retains its private IP. It is tempting because reservations reduce compute costs and guarantee capacity, which is the right choice when planning long-term, predictable workloads rather than performing host maintenance.
Go deeper
Related to this question
About these practice questions
One of 896 original 220-1101 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
Same concept, more angles
1 more way this is tested on 220-1101
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A company runs a critical application on a virtual machine (VM) in a public cloud. The application requires a static private IP address and persistent block storage that must be retained if the VM is replaced. Due to performance issues, the IT team needs to migrate the application to a new VM with more vCPUs and RAM. Which of the following actions will achieve this with minimal downtime while preserving the static IP and data?
medium- A.A) Create a new VM with the desired resources, then manually copy the application data over the network
- B.B) Migrate the existing VM to a different physical host within the same cloud region
- ✓ C.C) Detach the persistent storage volume from the old VM, create a new VM with the desired resources, attach the volume, and assign the static IP to the new VM
- D.D) Take a snapshot of the current VM and deploy a new VM instance from that snapshot, then reconfigure the IP
Why C: It directly addresses the requirements: detaching the persistent block storage (e.g., a cloud volume like an EBS or persistent disk) preserves the data independently of the VM lifecycle, and assigning the static private IP to the new VM maintains network identity. This approach minimizes downtime by avoiding data transfer over the network and allows the new VM to be provisioned with the desired vCPUs and RAM while the old VM remains running until the cutover.
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This 220-1101 practice question is part of Courseiva's free CompTIA certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 220-1101 exam.