A website migration can often be completed with little or no noticeable interruption if the new website is prepared before the domain is switched.
However, complete zero downtime cannot always be guaranteed because DNS changes, hosting issues or unexpected migration problems can occur.
1. Set up the new hosting first
Create the new hosting account and configure the website before changing your domain.
Do not cancel the existing hosting while the migration is still being tested.
2. Create a complete backup
Back up your current website, including its files, database and important media.
Keep the backup available throughout the migration in case you need to restore the original website.
3. Copy and test the website
Transfer the website to the new hosting environment while the existing website remains live.
Use a staging environment, temporary address or another suitable method to test the new site without changing the public domain.
Check important pages, images, forms, navigation and other functionality.
4. Reduce the DNS TTL beforehand
If you control the domain’s DNS settings, consider lowering the TTL (Time to Live) of relevant DNS records before the migration.
A shorter TTL can reduce how long some DNS resolvers retain the previous record, although it does not guarantee immediate propagation.
5. Plan the final switch
Choose a period when website activity is relatively low, particularly if the website receives frequent form submissions, orders or other changes.
For websites with changing data, plan how new information created during the final migration will be transferred or synchronised.
6. Change the DNS
Once the new website is fully tested, update the relevant DNS records or nameservers to point to the new hosting environment.
Keep the old hosting active while DNS changes propagate and visitors transition to the new server.
7. Monitor both environments
Check the website after the DNS change and monitor forms, transactions, errors and other important functions.
Do not immediately shut down the old hosting. Keep it available until you are confident that traffic is reaching the new website correctly.

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