CKA Practice Question: Cluster Architecture, Installation & Configuration
A DevOps engineer is designing a Kubernetes cluster for a production environment. Which of the following is a best practice for etcd deployment?
⚠ Common exam trap
A common mix-up: candidates assume 'more nodes = more redundancy' (Option B) or that 'simplicity is better' (Option A), without understanding that etcd's Raft consensus requires an odd number of members and that dedicated, fast storage is non-negotiable for production reliability.
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
✓
Deploy etcd on dedicated nodes with SSD storage.
Etcd is the Kubernetes cluster's primary data store, and its performance directly impacts the entire cluster's stability and responsiveness. Dedicated nodes prevent resource contention from other workloads, while SSD storage provides the low-latency, high-IOPS performance required for etcd's frequent write operations (especially with the default 1 MB write-ahead log). This isolation is a recommended best practice in the official Kubernetes documentation for production clusters.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Deploy etcd on exactly 2 nodes for simplicity.
Why it's wrong here
Deploying etcd on exactly two nodes is a poor design choice because it creates an unstable quorum. In a two-node cluster, if one node fails, the remaining node cannot form a majority (quorum of 2/2 or 1/2 is not possible for a majority vote), leading to a split-brain scenario where neither node can safely process writes. etcd requires a strict majority to ensure data consistency, making an odd number of nodes (e.g., 3, 5) essential for fault tolerance and preventing data corruption.
- ✗
Deploy etcd on all worker nodes to maximize redundancy.
Why it's wrong here
Co-locating etcd on all worker nodes, while seemingly offering redundancy, is highly discouraged due to significant resource contention. etcd is a critical control plane component that requires stable CPU, memory, and I/O performance, which can be severely impacted by the unpredictable workloads running on worker nodes. This setup risks degrading etcd's performance and stability, potentially leading to cluster unresponsiveness or outages, rather than maximizing effective redundancy.
- ✓
Deploy etcd on dedicated nodes with SSD storage.
Why this is correct
Deploying etcd on dedicated nodes with SSD storage is the recommended best practice for production Kubernetes clusters. Dedicated nodes ensure etcd has exclusive access to CPU, memory, and network resources, preventing interference from other workloads. Furthermore, etcd is highly sensitive to disk I/O latency, making fast SSD storage crucial for maintaining low write latencies, high throughput, and overall cluster stability and responsiveness.
- ✗
Deploy etcd on the same nodes as GPU-accelerated workloads.
Why it's wrong here
Deploying etcd on the same nodes as GPU-accelerated workloads is an inefficient and problematic design. GPU workloads are typically resource-intensive, consuming significant CPU, memory, and I/O, which can directly compete with etcd's critical need for stable resources. Moreover, using expensive GPU-equipped nodes for a control plane component like etcd is a wasteful allocation of specialized hardware, offering no benefit to etcd's operation while introducing performance risks and increasing infrastructure costs unnecessarily.
Go deeper
Related to this question
Learn chapter
Kubernetes Architecture Overview
Key term
Network Policies
A Kubernetes resource that controls how pods communicate with each other and with other network endpoints, acting as a firewall for pod-to-pod traffic.
Key term
Ingress Resources
Ingress Resources are Kubernetes API objects that manage external access to services inside a cluster, typically HTTP and HTTPS traffic, by defining rules for routing requests based on hostnames and paths.
About these practice questions
One of 302 original CKA 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 →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This CKA practice question is part of Courseiva's free CNCF 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 CKA exam.