It's possible to force the re-creation of a EC2 or RDS instance using cloudformation stacks?
My stack goes stuck in a point where simply destroying and creating the resource will fix it, instead of that I had to delete entire stack to continue work.
This issue hit me twice. First I created an AWS::RDS::Instance with some defaults and then tried to downgrade it to "EngineVersion" : "5.5". Changing this its suposed to happen with some interruption, but mysql instances cannot be downgraded from 5.6 to 5.5 so the stack was left in UPDATE_FAILED state and I cannot be able to recreate RDS without a nasty trick.
The other occurrence was that i have several "AWS::EC2::Instance" which downloads and executes an script from it's "UserData" obviously if Y change the downloaded script I must recrete the instance, and theres no way to do so. Once again I use the same nasty trick to get the machine recreated.
The nasty trick:
Instead of using an autoscaling group of one machine, I solved both problems changing the availability zone in the properties... but left me with a bad taste