Free CA-003 sample questions

Correct answer: Network Infrastructure Automation

Consul-Terraform-Sync (CTS) specifically addresses the pillar of Network Infrastructure Automation. It monitors the Consul catalog for changes in services (health status, IP addresses) and automatically triggers Terraform runs to update network infrastructure (like firewalls, load balancers) to reflect those changes.

Correct answer: All network traffic is denied by default; 'Web' can only communicate with 'Database' if an explicit Intention allows it, utilizing mutual TLS for identity verification.

This describes the core Zero Trust principle in Consul. Identity is based on mTLS certificates (not IP addresses), and the default posture is to deny all traffic unless explicitly authorized by Intentions.

Correct answer: Consul provides a real-time DNS interface where applications query a service name (e.g., db.service.consul) and receive the currently healthy IP addresses.

Consul acts as a distributed DNS server. When services register or deregister, the catalog is updated immediately. Clients querying the DNS interface receive dynamic, up-to-date records of healthy instances only.

Correct answer: API Gateway

The Consul API Gateway (or historically, Ingress Gateway) is designed to manage North-South traffic, controlling access from external clients into the service mesh.

Correct answer: Consul health checks are distributed; local agents perform checks on their services and forward status updates to servers, reducing network traffic.

This is a key architectural difference. Instead of a central server pinging every node (O(N) traffic), Consul distributes the responsibility. The local agent checks its local services and only transmits status changes, making it highly scalable.

Correct answer: Quorum: 3, Tolerance: 2 failures

Consul uses the Raft consensus protocol. For a cluster of N servers, quorum is (N/2)+1. For 5 servers, quorum is 3. The failure tolerance is (N-1)/2, which is 2. If 3 servers fail, only 2 remain, which is less than the quorum of 3, causing the cluster to stop processing writes.