Top 7 Linux Ops Interview Questions and How to Answer Them

The author recounts a recent Linux operations interview, listing the job description and requirements, then provides detailed answers to seven typical interview questions.

1. Self‑introduction

Keep it brief (3‑4 minutes), focus on recent work experience, technologies used, and avoid excessive personal details. Structure the talk around the resume to guide the interviewer's attention.

2. How to implement gray‑release

Gray release selects a subset of users to test a new version, collects explicit (forums, social media) and implicit (usage metrics) feedback, and decides whether to expand or roll back. Key components include:

User identification : IP, cookies for anonymous web apps; account IDs for logged‑in apps.

Target user selection strategy : based on geography, device specs, demographics, etc.; choose forced upgrade for minor changes, optional upgrade for major releases.

Data feedback : client‑side (performance, stability, usage) and server‑side metrics.

Rollback strategy : for web apps, simple; for client apps, use rapid re‑release to overwrite the problematic version.

Public‑relations support : monitor social channels for explicit feedback and combine with implicit data for decision‑making.

3. MongoDB familiarity and deployment size

Typical deployment uses a primary‑secondary replica set or a sharded cluster. A small setup often uses 3‑5 servers. The sharding architecture relies on a routing process mongos that knows data locations and forwards client requests to the appropriate shard.

4. Release and rollback with Jenkins

Release : configure Jenkins with source code location (SVN or Git), pull code, tag the release, compile if needed, then push the build artifact to a release server and distribute it to business servers.

Rollback : locate the desired version on the release server by its tag/number and redeploy it to the target servers.

5. Tomcat working modes

Tomcat, a JSP/Servlet container, can run in three modes: standalone servlet container, in‑process servlet container, and out‑of‑process servlet container. Requests arrive either from a front‑end web server (Apache, Nginx, IIS) or directly from browsers.

6. Monitoring solutions

The author’s current environment runs on Alibaba Cloud, using Alibaba Cloud Monitoring with built‑in templates for ECS, RDS, etc., plus custom alarm rules. A previous IDC environment used Zabbix, which offers rich graphs and auto‑discovery but requires a Zabbix agent on each monitored host.

7. Data backup strategy

Production systems employ primary‑secondary architectures for hot backup. For cold backup, a dedicated backup server can use rsync with inotify and scheduled jobs. Release packages are also retained on the release server for future rollback.

Interview preparation tips

Know your résumé inside out; be ready to discuss every listed skill.

Avoid pretending to know something you don’t; admit gaps honestly.

Study underlying principles rather than memorizing configuration files.

Review the job description and requirements thoroughly before the interview.

After the interview, record each question and research any unknown topics promptly.