I'm trying to set-up a process whereby we automatically pull and deploy the latest EPiServer packages every week. My concern is how to maintain site availability when there is a database update. How do others hanlde this?

My current thinking is to have a blue-green deployment:

• Maintain two sets of front-end servers and databases
• When starting a deployment stop the CMS / make it read-only (not sure how to do this yet...)
• Clone the live database (blue) into the alternative database (green).
• Deploy the new front-end(s) to the green servers. 
• Make an HTTP request to 'warm-up' the green servers. This should also trigger the database migratin (with automatic schema updates).
• Re-configure the load balancer to redirect traffic from the blue to green front-ends.

Can anyone offer any advice?