What Does Meituan Ask? 20 Must‑Know Linux Ops Interview Q&A

Meituan Linux Operations Engineer Interview Overview

Position: System Operations Engineer, Salary 15K‑30K, Beijing Chaoyang, 3‑5 years experience, any degree.

Job Responsibilities

Design and optimize operation solutions such as flexible disaster recovery, intelligent scheduling, elastic scaling, and attack mitigation.

Lead operability design of business architecture and participate in system design and implementation.

Develop efficient automation tools to improve operational efficiency.

Perform comprehensive performance optimization to maximize user experience.

Accurately calculate capacity and plan to reduce operating costs.

Explore and research new operation technology directions.

Qualifications

≥3 years ops experience with deep understanding of monitoring, automated deployment, capacity management, and automated disaster recovery.

In‑depth knowledge of Linux kernel, TCP/IP and common RPC protocols.

Proficient in 1‑2 languages such as C, PHP, Python, or Shell with development experience.

Strong communication, coordination, project management and responsibility.

High technical sensitivity, analytical mindset and passion for solving challenging problems.

Interview Questions & Answers

Common methods for installing and uninstalling Linux software Answer: rpm -e package.rpm (use --nodeps to ignore dependencies); yum remove package (not recommended because it may remove dependent packages); or from source directory run make uninstall or simply delete the installation directory.

Remote connection tools for Windows and Linux Command‑line tools: Xshell, SecureCRT, PuTTY, SSH. Graphical tools: Xmanager (requires service and port 177), VNC‑Viewer (Linux needs vncserver), Windows Remote Desktop (Linux needs xrdp and VNC).

How to modify Linux IP address, gateway and hostname IP/Gateway: edit /etc/sysconfig/network-scripts/ifcfg-eth0 , set IPADDR=192.168.1.100 and GATEWAY=192.168.1.1 with BOOTPROTO=static . Hostname: edit /etc/sysconfig/network and set HOSTNAME=mysql .

Script to back up /var/mylog daily at 5 AM, compress, and upload via FTP Answer (illustrated):

iptables related commands (Community contributions are welcome.)

How to improve MySQL security after a fresh installation Answer: change default port; restrict access with iptables; enforce strong passwords and host‑based access; secure root account; enable binary and slow‑query logs; set proper permissions on installation and data directories; remove unused accounts and test database.

MySQL master‑slave replication principle and configuration Replication steps: master writes changes to binary log; slave copies binary log events to relay log; slave replays relay log to apply changes. Detailed process includes IO thread connection, binlog position tracking, relay log writing, and SQL thread execution.

How to list all directories under /test Four methods are provided (image):

Compress all files in /etc/a except b into /home/a/a.gz Command: tar --exclude /etc/a/b -zPcvf /home/a/a.gz /etc/a

Give a script execution permission Command: chmod +x a.sh

Meaning of umask 022 Default permissions are calculated by subtracting the umask from the base mode (777 for directories, 666 for files). Thus new directories become 755 (rwxr-xr-x) and files become 644 (rw-r--r--).

How to view all files opened by a process Find the PID and run lsof -p PID (example shown for crond).

Capture packets on eth0 port 80 Command: tcpdump -i eth0 port 80

Delete all files and directories under /a/b Command: rm -rf /a/b/*

Common network management tools (≥5) Windows: ipconfig (/all, /renew, /release), ping, tracert, nslookup… Linux: ifconfig, ping, traceroute, dig, nslookup…

Ports for FTP, HTTPS, SMTP, POP3, SSH FTP 20/21, HTTPS 443, SMTP 25, POP3 110, SSH 22.

Enable >3 GB memory support on Windows Server 2003/2008 Add /PAE switch to the last line of boot.ini and reboot.

iptables rule to allow 192.168.1.2 access to port 80 Command: iptables -A INPUT -p tcp -s 192.168.1.2 --dport 80 -j ACCEPT

Shell script to create group “class” and users std01‑std30 belonging to it Script (image):

Show all MySQL client connections Command: show full processlist;

Delete expired MySQL binary logs Set expire-logs-days=7 in my.cnf and restart, or run purge binary logs to 'mysql-bin.000003'; or PURGE BINARY LOGS TO 'log_name';