Migrating a Website to a New Host Without Downtime

Introduction

Moving a website to a new host does not have to mean visible downtime. A good migration is prepared before DNS is changed. The website files and database should be copied to the new host, tested privately, secured with SSL, and only then switched live.

Most migration problems happen when DNS is changed too early, the database is not synced correctly, email DNS records are lost, SSL is not ready, or the old hosting is deleted before the new site is fully verified.

Quick answer

Website migration

Website migration means moving a website from one hosting environment to another. This can be a move from shared hosting to VPS, VPS to another VPS, one cPanel account to another, one data center to another, or one provider to another.

A no-downtime migration means users should continue seeing a working website during the move. In practice, the goal is to prepare the new hosting first, test it carefully, then make the DNS switch only after the new site is ready.

Before migration

Before moving anything, collect all required access and configuration.

You need:

• old hosting access
• new hosting access
• domain/DNS access
• database access
• FTP/SFTP/SSH access
• control panel access if available
• SSL certificate method
• email hosting details
• current DNS zone export
• website files backup
• database backup
• list of cron jobs
• list of redirects
• list of subdomains
• PHP/runtime version
• application configuration files

Lower DNS TTL

TTL controls how long DNS resolvers may cache a record. Lowering TTL before migration helps DNS changes spread faster when you switch to the new host.

Recommended approach:

• lower TTL 24–48 hours before migration when possible
• use a temporary TTL such as 300 seconds
• lower A, AAAA and CNAME records related to the website
• avoid changing MX records unless email is also moving
• restore normal TTL after migration is stable

Backups

Create a complete backup before changing the live site.

Back up:

• website files
• database
• uploads/media
• configuration files
• .htaccess or Nginx rules
• cron jobs
• redirects
• SSL notes
• DNS zone
• email DNS records
• application environment files

Copy files and database

After backup, copy the website to the new hosting environment.

For file-based websites:

• copy files to the correct web root
• preserve folder structure
• check file ownership
• check file permissions
• copy hidden files such as .htaccess

For database websites:

• export database from old host
• create database on new host
• import database to new host
• update database credentials in config
• check character set and collation
• test database connection

Test before DNS switch

The new site should be tested before public DNS points to it.

Testing methods:

• temporary URL from hosting provider
• staging subdomain
• hosts file preview
• server IP preview if supported
• control panel preview
• local DNS override

Check:

• homepage loads
• important pages load
• admin login works
• forms work
• database connection works
• images load
• CSS/JS loads
• internal links work
• redirects work
• no PHP errors
• no mixed content
• correct PHP version
• correct file permissions

SSL preparation

SSL should be ready as soon as traffic reaches the new host.

Options:

• Let’s Encrypt after DNS points
• DNS validation certificate before switch
• temporary certificate if supported
• CDN-managed certificate
• hosting panel AutoSSL

Check:

• certificate covers root domain
• certificate covers www if used
• HTTPS works after switch
• HTTP redirects to HTTPS
• no mixed content
• certificate renews automatically

Protect email

Website hosting and email hosting may be separate. A website migration should not break email.

Before changing DNS, copy:

• MX records
• SPF record
• DKIM records
• DMARC record
• autodiscover records
• mail subdomain records
• verification TXT records

Why this matters

A careful migration keeps both old and new environments available until the new host is verified and traffic has moved.

How to check readiness

Use Domain Health Checker, DNS Lookup, Website Status Checker and SSL Checker before and after switching.

1. DNS records — Confirm A, AAAA and CNAME records are ready.
2. Email records — Confirm MX, SPF, DKIM and DMARC are preserved.
3. New host preview — Test the website before public DNS switch.
4. SSL — Confirm certificate can be issued or is already ready.
5. Website status — Check homepage and important URLs.
6. Redirects — Check HTTP to HTTPS and www/non-www behavior.
7. Database — Confirm dynamic content works.
8. Forms and login — Test contact forms, admin login, checkout or customer areas.

Common problems

Migration steps

1. Step 1: Audit current hosting

   List files, database, DNS records, email records, PHP version, cron jobs and redirects.

2. Step 2: Lower website DNS TTL

   Reduce TTL before the migration window.

3. Step 3: Back up everything

   Download files, database and DNS zone backups.

4. Step 4: Prepare new host

   Create web root, database, PHP version, SSL plan and required services.

5. Step 5: Copy files and database

   Move website data and update configuration.

6. Step 6: Test privately

   Use temporary URL, staging subdomain or hosts file preview.

7. Step 7: Final database sync

   For dynamic sites, pause writes or sync recent changes before cutover.

8. Step 8: Switch DNS

   Update A/AAAA/CNAME records to the new host.

9. Step 9: Verify live site

   Check status, SSL, forms, redirects, login, media and important pages.

10. Step 10: Keep old host temporarily

    Do not cancel old hosting until DNS and traffic are stable.

WordPress migration notes

WordPress migrations need extra attention because content is split between files and database.

Check:

• wp-content folder
• uploads
• plugins
• themes
• wp-config.php
• database credentials
• serialized data if replacing URLs
• permalink settings
• .htaccess rules
• PHP version
• memory limit
• cache plugin
• security plugin
• SMTP plugin
• cron jobs
• WooCommerce orders if applicable

Hosts file preview

A hosts file preview lets you test the new server while the public domain still points to the old host.

New server IP:
192.0.2.10

Local hosts entry:
192.0.2.10 example.com
192.0.2.10 www.example.com

Rollback plan

A rollback plan helps you recover if the migration fails.

Before switching DNS, prepare:

• old host remains online
• old DNS values saved
• database backup available
• new host changes documented
• low TTL active
• access to DNS panel confirmed
• support contacts ready
• testing checklist ready

Post-migration checklist

Useful migration checks

Check DNS:
dig example.com A
dig www.example.com CNAME
dig example.com MX

Check website status:
curl -I https://example.com

Follow redirects:
curl -IL http://example.com

Preview new host with curl:
curl -I --resolve example.com:443:192.0.2.10 https://example.com

Check SSL:
openssl s_client -connect example.com:443 -servername example.com </dev/null 2>/dev/null | openssl x509 -noout -subject -issuer -dates

Check old HTTP:
curl -IL http://example.com

Frequently asked questions