Moving data between two servers without downtime requires some careful planning and execution. I’ve done this a thousand times, its also a good benchmark on the quality of your backups, so lets check my guidelines to a smooth server move!
Backup your old server – First, you need to make a fresh backup of your old server, this will guarantee that if something goes wrong you will still have a way to go back, you will have some downtime but nothing is loss, so start with a new backup.
Set up the new server – You need to prepare the new server to ensure it is fully configured and ready to receive the data. This includes installing the necessary software, configuring the server environment, and optimizing performance. Think of it as setting up a cozy new home for your data, complete with all the essential amenities.
Synchronise the data – To minimize downtime, you’ll want to synchronise the data between the old and new servers. This can be achieved through various methods, such as database replication or file synchronisation. i tend to ssh into the new server and rsync everything. It’s like making sure all your belongings are safely transported from your old house to the new one, ensuring nothing gets left behind.
Important Note Here, normally before starting the sync i put the old site in maintenance so there is no change or updates while the data is syncing, especially if the site is big or popular.
Test the migration – Before fully transitioning to the new server, it’s crucial to thoroughly test the migration process. This involves verifying that all data has been successfully transferred and that the new server functions correctly. Think of it as a dress rehearsal, where you ensure that everything runs smoothly before the big performance. I tend to use ssh with the diff command to achieve this.
Switch the DNS – Once you’re confident that the new server is ready to take over, you can update the DNS settings to point to the new server’s IP address. This step ensures that when users access your website or application, they are directed to the new server seamlessly. It’s like updating the address in your contact information so that people can find your new location without any hiccups.
Monitor and verify – After the DNS switch, closely monitor the traffic and performance on both servers. Keep an eye on any potential issues and ensure that the new server is handling requests correctly. Also make sure that other services dependent on that old server are transferred over like e-mail.
By following these steps, you can migrate data between servers with minimal to no downtime. However, it’s important to note that each migration scenario is unique, and careful planning and testing are crucial to ensure a smooth transition and always ALWAYS ALWAYS!!!!!! Have plenty of backups!