From [https://github.com/appc/spec/blob/master/spec/aci.md](https://github.com/appc/spec/blob/master/spec/aci.md):
>environment (list of objects, optional) represents the app's environment variables (ACE can append). The listed objects must have two key-value pairs: name and value. The name must consist solely of letters, digits, and underscores '_' as outlined in IEEE Std 1003.1-2008, 2016 Edition, with practical considerations dictating that the name may also include periods '.' and hyphens '-'. The value is an arbitrary string. These values are not evaluated in any way, and no substitutions are made.
Dotted environment variables are frequently used as a part of the Spring Boot pattern. (re: ZD-6116)
This PR specifically doesn't address the conversion of hyphens (`-`) due to an issue with rkt [[Nomad GH # 2358]](https://github.com/hashicorp/nomad/issues/2358).
Fixes an issue in which the allocation health watcher was checking for
allocations health based on un-interpolated services and checks. Change
the interface for retrieving check information from Consul to retrieving
all registered services and checks by allocation. In the future this
will allow us to output nicer messages.
Fixes https://github.com/hashicorp/nomad/issues/2969
This PR enhances the distinct_property constraint such that a limit can
be specified in the RTarget/value parameter. This allows constraints
such as:
```
constraint {
distinct_property = "${meta.rack}"
value = "2"
}
```
This restricts any given rack from running more than 2 allocations from
the task group.
Fixes https://github.com/hashicorp/nomad/issues/1146
This PR takes the host ID and runs it through a hash so that it is well
distributed. This makes it so that machines that report similar host IDs
are easily distinguished.
Instances of similar IDs occur on EC2 where the ID is prefixed and on
motherboards created in the same batch.
Fixes https://github.com/hashicorp/nomad/issues/2534
