CompTIA Cloud+ (CV0-004)DevOps FundamentalsMedium
A cloud administrator needs to update a fleet of 20 web servers behind a load balancer to a new application version without taking the service fully offline. The plan is to update a small batch of servers at a time, verify health, then move to the next batch until all servers run the new version. Which deployment strategy is being used?
- ACanary deployment
- BBlue-green deployment
- CRecreate deployment
- DRolling deployment
Show answer & explanationAnswer & explanation
Correct answer: D. Rolling deployment
A rolling deployment incrementally replaces instances of the old version with the new version in batches, keeping the service available throughout the process. Blue-green uses two full separate environments and canary targets a small user subset first, while recreate deployment takes everything offline before redeploying.
Why the other options are wrong
- A. Canary routes traffic to a small subset of users, not sequential server batches.
- B. Blue-green switches all traffic at once between two full environments, not gradual batches.
- C. Recreate deployment stops the old version entirely before starting the new one, causing downtime.
Rolling Deployment
A deployment strategy that gradually replaces instances of an old application version with a new version in small batches to maintain availability.
- Updates a subset of servers/pods at a time
- Minimizes downtime compared to full cutover
- Rollback requires reversing the batch process
Memory trick: Rolling stone gathers no downtime - it moves batch by batch.