101-acs-swarm - PropertyChangeNotAllowed and Blue/Green deployment

[101-acs-swarm] https://github.com/Azure/azure-quickstart-templates/tree/master/101-acs-swarm

Hi.

I want to have two Swarm clusters in the same Resource group to be able to add Load Balancer to this group and use it as "switcher" for kind of "Blue/green deployment". I.e. - to have two clusters in the same group, one as "PROD" and the second one - for "STAGE" ("Deployment slots" for WebApps).

I'm not sure if this is good idea/approach, but anyway - if I run provision with new `dnsPrefix` - I have an error:

`\\"code\\": \\"PropertyChangeNotAllowed\\",\\r\\n \\"target\\": \\"agentProfile.dnsPrefix\\",\\r\\n \\"message\\": \\"Changing property \'agentProfile.dnsPrefix\' is not allowed.\\"`

What I'm doing wrong here?
What is a better way to achieve "Blue/Green" deployment?

Thanks.

Start with the 101-acs-swarm template linked in the issue and review the deployment parameters around agentProfile.dnsPrefix. Reproduce the reported PropertyChangeNotAllowed error, then determine what the template supports for multiple clusters and what guidance is needed for the proposed blue/green setup.

Written by the indexing model from the issue text.