Add a whitelist meachanism so that only hosts that connect to Dali with matching roles are allowed to proceed.
When a client is refused, return an error and print it client side.

The whitelist will automatically be populated with the server components with their roles.

Example pseudo whitelist:

{ HostA, ThorMaster }
{ HostB, EclAgent }
{ HostC, Dali }
{ HostD, Roxie1 }

In addition to the auto population of the white list from existing component instances in the environment, a supplementary white list definition in the environment, will allow additional nodes and roles to be added, e.g. so that a daliadmin from an administrators node can be added.

This will look like, e.g:

hosts and roles can be single values, or a comma separated list of values.
This example specifies that DaliDiag and DaliAdmin roles are allowed to connect from adminnode1 and adminnode2.
And that DaliAdmin is allowed to connect from adminnode3.

Possible role values are:

The whitelist checks can be disabled completely by adding enabled="false" as an attribute to WhiteList, e.g.:

The current whitelist state can be retreived with: