After the managed.com issues we have had clients asking about the option to have a mirror instance of their sites on a separate failover server that would be accessible if the pimary server was down. 

We had discussed this once before with Managed and were told that we would need a full version license of SQL on both servers to be able to sync the databases constantly for any changes on either the primary or the failover. Currently we are using SQL express, and each of our sites are separate DNN instances not setup as portals. The SQL license on both servers was costly if I remeber somewhere around $400 a month per box. Seems to be similar pricing with AWS and others. 

I was looking to see if anyone had done any of this successfully, and if anyone had any thoughts on other options. I am NOT a developer, I am one of the owners of our firm but my developer has been looking at options, but wanted to reach out to the community for thoughts, advice etc. I was not sure if we could have a failover that could be up and running from a backup that pushed daily to a failover, so it would not be a constant sync but it would be less than a day old. That would be better than nothing, but costs are important, as we do not want to jackup hosting rates for clients substantially to offer this. 

Also open to any other tools others are using for disaster recovery, ways to automate standing up a site from a backup or other ideas, if we did have another situation like this and we have 30-50 sites we needed to get back online as quickly as possible.