Stacks & Clusters
General
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This view give you a general view of the Stack or Cluster, showing name, UUID and the type.
Elements
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The elements view only exists for Stacks, here you can add and remove clusters to the stack.
Configuration
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Each Stack or Cluster can have some configuration attached to it that can be accessed from the VM to have a tiny shared storage space. Values for that can be set here.
Creation
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This dialogue lets you create a new Stack or Cluster, Select the type you want and give it a name.
Example
Let us walk through it on a simple example, a web app - lets call it appy - it consists of:
psql (db), erlang (some app), haproxy (reverse proxy).
Which is a common setup but the same logic apply to every other combination of tools.
So the first step of the deployment is to create a stack for this application, lets call the stack appy, just like the application itself.
Now for each part of our application we create a cluster.
appy-db
appy-app
appy-proxy
Then we assign all those clusters to the stack as parts of it so we get a bit of a tree structure:
appy
-appy-db
-appy-app
`-appy-proxy
Now when creating a new zone it simply goes into the cluster that represents it's functionality. So a app server vm gets created in the appy-app cluster.
But things are not always static, while clusters can't change stacks can. Say the appy team gets all fancy and wants to extract the authentication in a own service form the main app it still is simple.
We create a new cluster appy-auth and join it to the appy stack so they'd have:
appy
-appy-db
-appy-app
-appy-proxy
-appy-auth
Now they can create a new VM in the appy-auth cluster and it'll be part of the stack like all the others and move the auth part of the app into there.
Updated less than a minute ago