Infrastructure engineer

What does an infrastructure engineer do?

An infrastructure engineer builds and looks after the servers, networks, storage and cloud services that applications run on.

The work covers on-premise systems, cloud platforms and the links between them.

In a Singapore organisation, the role sits in the IT or technology operations team. Banks, government agencies, telcos, hospitals and software firms all hire for it. Smaller firms may fold it into a wider systems role.

You work with software developers, security teams, network engineers, vendors and the service desk. You usually report to an infrastructure or IT operations manager.

What the work involves

• Carry out approved changes and upgrades to servers, storage, back-up systems and network equipment.
• Watch performance, availability and cost data, then adjust capacity before users notice problems.
• Write and update infrastructure code and scripts so environments can be rebuilt the same way each time.
• Respond to incidents, find the cause and write up what happened and how it was fixed.
• Update runbooks and records, and support disaster recovery tests and audit checks.

Pay in Singapore

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Skills an infrastructure engineer needs

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Infrastructure engineer job description

We are hiring an infrastructure engineer to deploy, run and improve our servers, network and cloud environments.

You will carry out upgrades, monitor performance, resolve incidents and keep documentation current. You will work with development, security and operations teams to meet agreed service standards.

Responsibilities

• Deploy and configure servers, virtual machines, containers and cloud resources to agreed designs.
• Carry out infrastructure change requests and routine maintenance with minimal disruption to users.
• Write infrastructure as code and automation scripts to cut manual work in upgrades, back-ups and provisioning.
• Monitor performance, reliability, availability, security and cost, and right-size resources when needed.
• Analyse hardware, software and network issues, and report limits of current infrastructure to your manager.
• Resolve infrastructure incidents, find the root cause and train other team members on the fix.
• Take part in disaster recovery planning and regular recovery tests.
• Keep installation, configuration and troubleshooting documents accurate and ready for audit.
• Apply security patches and access controls in line with company policy.
• Work with vendors on equipment, licences and support cases.

Requirements

• Diploma or degree in information technology, computer science, computer engineering or a related field, or equivalent work experience.
• Typically 1 to 3 years of experience for an engineer role. Entry roles may accept fresh graduates or career switchers with projects to show.
• Working knowledge of Linux administration and core networking, including DNS, routing, firewalls and load balancing.
• Hands-on use of at least one major cloud platform (AWS, Azure or Google Cloud) and an infrastructure as code tool such as Terraform.
• Familiarity with containers and Kubernetes, plus scripting in Bash or Python.
• Willingness to join an on-call rota and handle maintenance work outside office hours.

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Infrastructure engineer career path

Most infrastructure engineers start in a support or associate role and move up through hands-on engineering to team leadership.

Some move sideways into cloud, security or architecture.

1. Associate infrastructure engineer

   Entry · SkillsFuture title

   You carry out routine changes, monitoring and maintenance under guidance, and learn the organisation's systems and tools.

2. Infrastructure engineer

   Mid · SkillsFuture title

   You deploy and optimise infrastructure on your own, handle incidents and write automation and documentation.

3. Senior infrastructure engineer

   Senior

   You design solutions, lead complex upgrades and migrations, and coach junior engineers.

4. Infrastructure engineering manager

   Lead · SkillsFuture title

   You lead the team, plan budgets and vendors, and own service standards and disaster recovery.

5. Head of infrastructure

   Head

   You set the infrastructure direction for the organisation and answer to senior technology leaders.

Steps marked "SkillsFuture title" follow the career pathway in the SkillsFuture Skills Framework. The others are titles commonly used in Singapore.

Related jobs and their pay

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Infrastructure engineer interview questions

We wrote these questions from the skills this job needs. They are not an official question bank.

1. A Linux production server is slow and the load average is high. How do you find the cause?

   What a good answer covers

   • Checks load, CPU, memory, disk and network with tools such as top, vmstat, iostat and ss
   • Separates CPU-bound, memory pressure and disk wait problems
   • Reads system logs and recent change records
   • Finds the offending process before restarting anything
   • Records the cause and a follow-up fix

2. Design a virtual network for a web application and its database. How do subnets, routing and firewall rules work?

   What a good answer covers

   • Puts the web tier in public subnets and the database in private subnets
   • Explains route tables, gateways and NAT for outbound traffic
   • Limits traffic with security groups or firewall rules on least privilege
   • Covers DNS and load balancing
   • Mentions spreading across availability zones

3. What is Terraform state, and how does a team manage it safely?

   What a good answer covers

   • Explains that state maps code to real resources
   • Uses a remote backend with locking instead of local files
   • Restricts access because state can hold sensitive values
   • Separates state by environment or component
   • Reviews plan output before applying

4. A colleague changed a firewall rule by hand in the cloud console. How do you detect and handle the drift?

   What a good answer covers

   • Runs a plan or drift detection to compare code with live resources
   • Decides whether to revert the change or add it to code
   • Talks to the colleague about the reason for the change
   • Limits console write access and uses pull requests for changes
   • Adds scheduled drift checks

5. A Kubernetes pod is stuck in CrashLoopBackOff. What do you check?

   What a good answer covers

   • Reads pod events with describe and the container logs, including the previous run
   • Checks the image, command, environment variables and secrets
   • Looks at resource limits and out-of-memory kills
   • Checks liveness and readiness probes
   • Rolls back if the change was recent

6. How do you decide between virtual machines, containers and a managed cloud service for a new workload?

   What a good answer covers

   • Weighs control, effort to operate, cost and scaling needs
   • Considers the skills the team already has
   • Notes lock-in and portability
   • Checks security and compliance needs
   • Starts with the simplest option that meets the need

7. You use an AI coding assistant such as Claude Code to draft Terraform. How do you check what it produces?

   What a good answer covers

   • Reads every change as if a colleague wrote it
   • Runs plan in a test environment and reviews what will change
   • Checks for open access, hard-coded secrets and wrong regions
   • Runs linting and policy checks
   • Keeps real credentials and customer data out of prompts

8. How would you plan back-up and disaster recovery for a production database server?

   What a good answer covers

   • Defines recovery point and recovery time objectives with the business
   • Chooses back-up types, frequency and off-site or cross-region copies
   • Tests restores on a schedule as well as back-ups
   • Documents the recovery steps
   • Reports test results to management

1. A change you deployed in the evening has caused an outage for a customer-facing system. What do you do first?

   What a good answer covers

   • Tells the incident lead and affected teams quickly
   • Checks whether a rollback is the fastest safe fix
   • Keeps a timeline of actions taken
   • Confirms recovery with monitoring
   • Writes a review of the cause and prevention steps afterwards

2. The monthly cloud bill has risen sharply. How do you find out why and bring it down?

   What a good answer covers

   • Breaks cost down by account, service and tag
   • Looks for idle, oversized or forgotten resources
   • Checks for changes in traffic or storage growth
   • Proposes right-sizing, scheduling or reserved capacity with the risks
   • Sets alerts and tagging rules to catch it earlier

3. You must move 40 on-premise virtual machines to the cloud with little downtime. How do you plan it?

   What a good answer covers

   • Lists systems, dependencies and owners first
   • Groups workloads into waves and starts with low-risk ones
   • Plans network links, data transfer and cut-over windows
   • Prepares a rollback plan for each wave
   • Tests with users before switching traffic

1. Tell us about an incident you helped resolve. What did you learn from it?

   What a good answer covers

   • Describes the impact and your own part clearly
   • Explains how the cause was found
   • Shows calm communication under pressure
   • Names a lasting fix, such as an alert or a runbook
   • Focuses on causes, not on blaming individuals

2. Describe a time you had to push back on a change request or deadline. How did you handle it?

   What a good answer covers

   • States the technical risk without jargon for non-technical people
   • Offers an alternative to a flat no
   • Gets agreement from the right owners
   • Follows up on the result

1. Servers you manage hold customer personal data. Which infrastructure controls would you put in place to support Personal Data Protection Act (PDPA) obligations?

   What a good answer covers

   • Limits access by role and logs who accessed what
   • Encrypts data at rest and in transit
   • Defines retention and secure deletion
   • Knows to alert the data protection officer quickly if a breach is suspected
   • Takes care when data is hosted or backed up outside Singapore

2. A bank client asks how your cloud set-up supports resilience under Monetary Authority of Singapore (MAS) technology risk expectations. What evidence do you prepare?

   What a good answer covers

   • Shows recovery objectives and the results of recovery tests
   • Documents change control, access reviews and monitoring
   • Explains how single points of failure are avoided
   • Shows vendor and outsourcing arrangements
   • Checks the current MAS requirements with the compliance team

Common questions about an infrastructure engineer job

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