174 Essential Operations Engineer Interview Questions You Must Master

I spent a week interviewing at dozens of internet companies, focusing on Linux, container operations, and automation, including IBM, Sina, and Perfect World, and compiled the following interview questions to help others prepare.

174 Operations Engineer Interview Questions

What is operations? What is game operations?

What does an operations person do when working with product teams?

Given three hundred servers, how would you manage them?

Explain the principles and characteristics of RAID0, RAID1, and RAID5.

What are the differences between LVS, Nginx, and HAProxy, and how do you choose among them?

What are the differences between Squid, Varnish, and Nginx, and how do you choose?

What are the differences between Tomcat and Resin, and how do you choose?

What is middleware? What is JDK?

Explain the meanings of Tomcat ports 8005, 8009, and 8080.

What is a CDN?

What is gray‑release for a website?

Describe the DNS domain resolution process.

What is RabbitMQ?

Explain how Keepalived works.

Describe the three LVS working modes.

How does MySQL InnoDB locate lock issues, and how can MySQL reduce master‑slave replication lag?

How to reset the MySQL root password?

Advantages and disadvantages of LVS, Nginx, HAProxy.

MySQL data backup tools.

How Keepalive performs health checks.

Analyze Nginx access logs to list the top ten IPs by request count.

Use tcpdump to capture traffic on host 192.168.1.1 port 80 and save to tcpdump.log.

Forward local port 80 requests to port 8080 on host 192.168.2.1.

Explain RAID0, RAID1, RAID5 principles and features.

What is your understanding of the operations engineer role?

Write a command to capture and display real‑time TCP port 80 network data.

Step‑by‑step troubleshooting for a server that won’t boot.

How to handle a virus infection on a Linux system.

If a virus file re‑creates after deletion, how to resolve it?

Explain the OSI seven‑layer model.

Which Nginx modules do you commonly use and for what purpose?

List web server load‑balancing architectures you know.

How to view HTTP concurrent request count and TCP connection states.

Use tcpdump to sniff port 80 and identify the highest traffic source.

Write a script to list online IPs in 192.168.1.0/24 by ping response.

Given Apache logs in /app/logs, keep only the last 7 days due to disk space constraints – provide a solution.

How would you optimize a Linux system (general ideas)?

Extract the IP address of eth0 using cut (or awk/sed).

Explain the function of a specific SecureCRT shortcut command.

Schedule a nightly backup of /var/www/html to /data with timestamped archives.

Mount a Windows shared directory on Linux.

Check HTTP concurrent requests and TCP connection states (duplicate).

Use tcpdump to sniff port 80 and identify the highest traffic source (duplicate).

Count files in /var/log.

Count connections per IP on the current system.

Generate a random 32‑bit password in shell.

Find the top 5 IPs by request count in Apache access.log.

How to view the contents of a binary file.

What do VSZ and RSS represent in ps aux output?

Detect and repair /dev/hda5.

Explain Linux boot sequence.

Difference between symbolic and hard links.

Save current disk partition table.

Copy, paste, delete lines, and search in a text file.

Manually install GRUB.

Extract lines 4‑7 from file aaa.txt.

List files ending with .txt in the current directory.

Find files larger than 1 MB under /usr.

Create a cron job to run between 5 am and 8 am.

Explain MySQL master‑slave replication principles.

How many modes does Vim have?

Describe the DNS resolution process for www.baidu.1.com.

Explain the two DNS query modes.

Describe forward and reverse proxy.

Summarize ETCD and its characteristics.

Typical scenarios for using ETCD.

Summarize HAProxy and its features.

Common HAProxy load‑balancing strategies.

Difference between layer‑4 and layer‑7 load balancing.

Differences among LVS, Nginx, HAProxy.

Explain Heartbeat.

Explain Keepalived and its working principle.

Key modules of Keepalived and their functions.

How Keepalived ensures high availability via health checks.

Concept and role of LVS.

LVS working modes and processes.

Common LVS scheduling algorithms.

Pros and cons of LVS, Nginx, HAProxy.

Concept and role of proxy servers.

Metrics for evaluating high availability.

Explain CAP theorem.

Explain ACID properties.

What is Kubernetes?

Relationship between Kubernetes and Docker.

Kubernetes components: minikube, kubectl, kubelet.

Common Kubernetes deployment methods.

How Kubernetes manages clusters.

Kubernetes advantages, suitable scenarios, and characteristics.

Kubernetes drawbacks and current limitations.

Fundamental Kubernetes concepts.

Kubernetes cluster components.

Kubernetes ReplicationController mechanism.

Difference between ReplicaSet and ReplicationController.

Role of kube‑proxy.

kube‑proxy iptables principle.

kube‑proxy IPVS principle.

Differences between kube‑proxy IPVS and iptables.

What is a static Pod in Kubernetes?

Possible Pod states in Kubernetes.

Process of creating a Pod.

Pod restart policies.

Pod health‑check methods.

Common LivenessProbe implementations.

Typical Pod scheduling methods.

Init containers purpose.

Kubernetes Deployment upgrade process.

Deployment upgrade strategies.

DaemonSet resource characteristics.

Kubernetes auto‑scaling mechanism.

Kubernetes Service types.

Service backend distribution strategies.

Headless Service concept.

External access to cluster services.

Ingress overview.

Image download strategies.

Kubernetes load balancer.

How Kubernetes modules communicate with the API server.

Scheduler role and implementation principle.

Scheduler algorithms for binding Pods to nodes.

Kubelet role.

Kubelet monitoring of worker node resources.

How Kubernetes ensures cluster security.

Admission control mechanisms.

Kubernetes RBAC features and advantages.

Purpose of Kubernetes Secrets.

Ways to use Secrets.

PodSecurityPolicy mechanism.

Security policies achievable with PodSecurityPolicy.

Kubernetes network model.

Kubernetes CN model.

Kubernetes network policies.

Principles of network policies.

Role of Flannel in Kubernetes.

How Calico works.

Purpose of shared storage in Kubernetes.

Ways to achieve data persistence.

Kubernetes PV and PVC concepts.

PV lifecycle stages.

Supported storage provisioners.

Kubernetes CSI model.

Process for a worker node joining a cluster.

How Pods control node resource usage.

Impact of Requests and Limits on scheduling.

Kubernetes Metric Service overview.

Using EFK for unified log management.

Graceful node shutdown maintenance.

Kubernetes cluster federation.

Helm and its advantages.

OpenShift overview and features.

OpenShift projects purpose.

OpenShift high‑availability implementation.

OpenShift SDN network implementation.

OpenShift roles and responsibilities.

Supported authentication methods in OpenShift.

What is middleware?

Disk usage detection with shell script.

LVS load‑balancing strategies.

Your understanding of LVS.

Principles of load balancing.

Components of LVS.

Terms related to LVS.

LVS‑NAT principle.

Features of LVS‑NAT model.

LVS‑DR principle.

Features of LVS‑DR model.

Comparison of three LVS load‑balancing modes.

LVS scheduling algorithms.

Differences between LVS and Nginx.

Roles of load balancing.

Nginx load‑balancing distribution strategies.

What is Keepalived?

Understanding of VRRP protocol.

Keepalived working principle.

Causes of split‑brain scenarios.

How to resolve Keepalived split‑brain issues.