dns

README

DNS Controller

The DNS Controller orchsterates the configuration needed to setup the ATE routing.

We want to resolve requests for .actors.resources.substrate.ate.dev to the router service address.

• Stub resolver mode: orchestrate running a CoreDNS instance with the UUID mapped to the router service address.

Cluster resources:

• Deployment ate-system:dns. Label: app=dns
• Service ate-system:dns.
• ConfigMap ate-system:dns.

These are defined in manifests/ate-install/atenet-dns.yaml.

Stub resolver mode

• Ensure stub resolver CoreDNS is running as:
  • Deployment ate-system:dns.
  • Service ate-system:dns pointing to the Deployment.

ConfigMap ate-system:dns:

# Match any 'A' query for a UUID pattern under actors.resources.substrate.ate.dev
    template IN A actors.resources.substrate.ate.dev {
        match "^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}\\.actors\\.resources\\.substrate\\.k8s\\.io\\.$"
        answer "{{ .Name }} 60 IN A <router service address>"
    }

Integration

• CoreDNS: Update CoreDNS ConfigMap to add the stub resolver.
• GKE DNS: Update the GKE DNS ConfigMap to add the stub resolver.

Documentation

Index

• type ConfigReloader
  • func NewConfigReloader() ConfigReloader
• type Controller
  • func (c *Controller) Run(ctx context.Context) error

Types

type ConfigReloader

type ConfigReloader interface {
	Reload(ctx context.Context) error
}

ConfigReloader defines an interface for dynamically signaling CoreDNS to reload its configuration.

func NewConfigReloader

func NewConfigReloader() ConfigReloader

type Controller

type Controller struct {
	Client       client.Client
	Interval     time.Duration
	CorefilePath string
	Reloader     ConfigReloader
}

Controller manages the DNS configuration for the ATE.

func (*Controller) Run

func (c *Controller) Run(ctx context.Context) error

Run the DNS orchestration loop until ctx is canceled.