Hosting and Deployment Interview Questions for Web Development
23 Hosting and Deployment questions with answers for web development roles — 4 easy, 12 medium, 7 hard.
About Hosting and Deployment
A web developer must take code live and keep it running. This topic covers shared, VPS and cloud hosting, DNS records, CDNs, Apache and Nginx, SSL certificates, Git-based deployment, cron jobs and CI/CD with GitHub Actions, along with outage scenarios like 502 errors, full disks and traffic spikes.
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Shared hosting puts many sites on one server with a control panel like cPanel; it is cheap and easy but offers limited resources and control. A VPS gives you a virtual machine with root access, dedicated RAM and CPU, so you install and secure the stack yourself. Cloud platforms like AWS, Azure and Google Cloud add auto-scaling, managed databases and pay-per-use pricing, suited to growing applications.
An A record maps a domain to an IPv4 address and AAAA to IPv6. CNAME points one name to another, such as www to example.com, but cannot sit on the root domain. MX records route email to mail servers. TXT records hold verification and email security data like SPF, DKIM and DMARC. NS records name the authoritative nameservers. TTL controls how long resolvers cache each record.
03
You changed DNS to a new server but some users still see the old site. Why?
DNS resolvers and browsers cache records for the TTL period, so changes propagate gradually; with a high TTL like 24 hours, some users keep the old IP for a day. I would check with dig or an online DNS checker from several locations. Best practice is lowering the TTL to 300 seconds a day before migration, keeping the old server running until traffic drains, and then raising the TTL again.
I enjoy building things people use directly. During college, I made a website for a local library, and seeing members search books online gave me real satisfaction. Web development lets me combine design with logic, from HTML and CSS to PHP and MySQL, and see results immediately. I want to grow in a team that ships real products and eventually take ownership of complete features end to end.
A content delivery network caches static files such as images, CSS and JavaScript on servers in many locations, so a user in Chennai is served from a nearby edge rather than a distant origin. This reduces latency, lowers load on your server and absorbs traffic spikes and some DDoS attacks. Cache-Control headers decide how long files stay cached, and versioned filenames let you deploy updates without stale content.
06
What are the differences between Apache and Nginx?
Apache uses a process or thread based model and supports per-directory .htaccess files, which is convenient on shared hosting. Nginx uses an event-driven model that handles many concurrent connections with low memory, making it excellent for static files and as a reverse proxy. Nginx runs PHP through PHP-FPM and has no .htaccess, so rules go in central config. Many setups put Nginx in front of Apache or application servers.
07
How do SSL/TLS certificates work, and what is Let's Encrypt?
A TLS certificate proves a server owns a domain and enables encrypted HTTPS connections. During the handshake, the browser verifies the certificate chain against trusted authorities, and both sides agree on session keys. Let's Encrypt is a free, automated certificate authority; tools like Certbot request and renew its certificates, which are valid for about 90 days. Automatic renewal through cron or systemd timers prevents expiry outages.
08
Write .htaccess rules to force HTTPS and the non-www domain.
On Apache with mod_rewrite enabled:
RewriteEngine On
RewriteCond %{HTTPS} off [OR]
RewriteCond %{HTTP_HOST} ^www\. [NC]
RewriteCond %{HTTP_HOST} ^(?:www\.)?(.+)$ [NC]
RewriteRule ^ https://%1%{REQUEST_URI} [L,R=301]
A 301 redirect tells search engines the change is permanent, so ranking signals move to one canonical URL. Test carefully, because a wrong rule can cause a redirect loop behind a proxy or load balancer.
A simple scripted deployment:
ssh deploy@server.example.com << 'EOF'
cd /var/www/app
git pull origin main
composer install --no-dev --optimize-autoloader
php artisan migrate --force
php artisan config:cache
sudo systemctl reload php8.3-fpm
EOF
Use an SSH key, not a password, and a non-root deploy user. Reloading PHP-FPM clears OPcache so new code is served. For safer releases, deploy into a new folder and switch a symlink.
Edit the crontab with crontab -e and add:
30 2 * * * mysqldump --single-transaction -u backup school | gzip > /backups/school_$(date +\%F).sql.gz
0 3 * * * find /backups -name '*.sql.gz' -mtime +14 -delete
The first line runs at 2:30 AM daily; the second removes backups older than 14 days. Keep credentials in ~/.my.cnf with restricted permissions instead of the command, escape % in crontab, and copy backups to off-server storage.
11
Your site suddenly shows 502 Bad Gateway. How do you troubleshoot it?
502 means Nginx could not get a valid response from the upstream, usually PHP-FPM or an application server. I would check if the service is running with systemctl status php8.3-fpm, read the Nginx error log and the PHP-FPM log, and confirm the socket path in the config matches. Common causes are crashed workers, exhausted pm.max_children, memory limits or a recent config change. Restarting brings it back, but the root cause must be fixed.
12
The server's disk is full and the site has stopped saving data. What do you do?
I would check usage with df -h and find large folders using du -sh /var/* | sort -h. Usual culprits are huge log files, old backups, cached uploads or MySQL binary logs. I would safely clear or compress logs, purge old binlogs with PURGE BINARY LOGS, and move backups off the server. To prevent repeats, set up logrotate, backup retention and disk usage alerts at about 80 percent.
13
Emails sent from your website contact form land in spam. How do you fix it?
I would stop sending through PHP mail() from the web server and use an authenticated SMTP or transactional email service. Then I would publish SPF to authorise the sender, DKIM to sign messages, and a DMARC policy in DNS. The From address should belong to the verified domain, while the visitor's email goes in Reply-To. Mail testing tools show the spam score and missing records.
14
Time to first byte is over 2 seconds even for simple pages. What do you check?
High TTFB points to the server, not the browser. I would check if OPcache is enabled, profile slow database queries, look for blocking external API calls during page generation, and check whether the server is low on CPU or memory. Fixes include full-page caching for anonymous users, object caching with Redis, upgrading PHP, choosing a server region close to Indian users, and putting a CDN in front.
15
Tell me about a time a website went down and how you handled it.
Situation: our e-commerce site went down at 11 PM during a sale. Task: as the on-call developer, I had to restore it fast. Action: I checked logs, found PHP-FPM workers exhausted by a slow query, restarted the service, added an index to fix the query, and kept the team updated every 15 minutes. Result: the site was back in 20 minutes, and I wrote a postmortem with monitoring alerts to catch it earlier.
16
A client insists on a major deployment on Friday evening. How do you respond?
Situation: a client wanted a big redesign live before a weekend campaign. Task: I had to respect their goal but reduce risk. Action: I explained that weekend issues would have fewer people to fix them, proposed deploying Thursday morning on staging-tested code, and arranged a rollback plan and someone on call. Result: the client agreed, we deployed Thursday, fixed two small issues the same day, and the campaign ran smoothly.
17
Write an Nginx server block for a PHP application using PHP-FPM.
I would load test with tools like k6 or JMeter to find the breaking point, then cache result pages aggressively using a CDN and Redis. The database should have proper indexes, and read-heavy queries could go to replicas. On cloud, I would configure auto-scaling and pre-warm extra instances before the announcement. A lightweight static fallback page and a queue for heavy tasks keep the site responsive under peak load.
20
How would you deploy updates without any downtime?
I would use atomic releases: upload the new version into a fresh release folder, install dependencies and build assets there, then switch a current symlink in one step and reload PHP-FPM. Database migrations must be backward compatible, such as adding columns before code uses them, so old and new code both work during the switch. With multiple servers, rolling or blue-green deployment behind a load balancer achieves the same.
21
A client wants to move a growing site from shared hosting to a VPS. How do you plan the migration?
I would set up the VPS with Nginx, PHP-FPM, MySQL, firewall and SSL, matching PHP versions and extensions. Then I would copy files with rsync, export and import the database, and test the site using a hosts file entry before touching DNS. After lowering the TTL, I would do a final data sync during low traffic, switch DNS, monitor logs, and keep the old hosting live for a few days as fallback.
22
How do you manage configuration and secrets across local, staging and production?
I keep code identical across environments and change only configuration through environment variables, usually loaded from a .env file that is never committed. A .env.example documents required keys without values. In production, secrets live in the server environment, the CI secret store or a cloud secrets manager. Each environment has separate database credentials and API keys, so a staging leak cannot affect production.
23
How have you helped a junior developer learn deployment?
Situation: a new joiner was nervous about deploying to production. Task: I was asked to make them independent within a month. Action: I wrote a step-by-step deployment checklist, let them deploy to staging while I watched, then paired on two production releases with them driving. Result: they handled releases alone after three weeks and later improved our checklist with a rollback section.
Frequently asked questions
How important is Hosting and Deployment in Web Development interviews?
A web developer must take code live and keep it running. This topic covers shared, VPS and cloud hosting, DNS records, CDNs, Apache and Nginx, SSL certificates, Git-based deployment, cron jobs and CI/CD with GitHub Actions, along with outage scenarios like 502 errors, full disks and traffic spikes.
How should I use the Hosting and Deployment sheet?
Go top to bottom — easy to hard. Answer before opening each answer, tick what you solved and save misses to Last-Minute Revision.