As this technique requires several “moving parts”, your selection of Hosting providers is vital as they will need to offer the services that you need along with the support necessary to make configuration changes that you can not make in a typical shared hosting environment.
- Your Production Server
Your production web server will need to allow SSH access.
- Your Mirror Server
Your mirror server will need to be located in a different geographical location than your production server. In addition, your web host must allow the following:
And, when you/they setup your account make sure of these details:
- Your mirror account username must match the username of your production server.
(This is important when you are syncing MySQL databases as it makes it much easier if your databases share the same name, and as you CPanel users know, CPanel database names are typically appended with the username associated with the server e.g. jsmith_).
- Setup your mirror account with its name being a subdomain of your production server’s domain (e.g. production = yahoo.com; mirror = mirror.yahoo.com; I had to ask my host to do this for me).
- Park your production domain on top of your mirror account. This way when your fail over switching gets activated your mirror server will serve up its website. (The CPanel may throw an error when you try to park yourdomain.com on top of mirror.yourdomain.com. In that case, submit a support ticket to your web host.)
Finally, once your mirror account is active, edit the DNS for your production domain and add an A record with your mirror’s subdomain pointing it to the IP address of your mirror.
- DNS Failover
You will need a DNS service that provides some sort of “DNS Fail Over Switching”. This is exactly the type of service that DNS Made Easy provides. Their service lets you create multiple A records for a domain. Then their DNS Failover system will monitor the server located at your first A record. If that server goes down, the Fail Over switching will automatically switch your domain to point to the second IP address on the list. I have tested their switching with my mirror, and I have found that their DNS records typically propagate within 25 minutes.
Once you have these three pieces, you are now ready to proceed to Step 2: Setting Up Keys and Authentication