Consul DNS use cases

Consul DNS is the primary interface for querying records when Consul service mesh is disabled and your network runs in a non-Kubernetes environment. Consul DNS lets you look up services and nodes registered with Consul without making HTTP API requests to Consul. We recommend using the DNS for service discovery in virtual machine (VM) environments because it removes the need to modify native applications so that they can consume the Consul service discovery APIs. The DNS has several default configurations, but you can customize how the server processes lookups. Refer to Configure Consul DNS behavior for additional information.

For reference information about formatting Consul DNS requests, refer to Consul DNS reference.

Consul DNS dolves the following primary use cases:

• Multi-cloud service discovery at scale: Consul DNS provides a single domain name addresses that works across multi-cloud and hybrid cloud environments where Consul runs. You can scale application workloads using ephemeral services that are always addressable through Consul.
• Fine-grain DNS options: You can address a service running in a specific datacenter, admin partition, or namespace. You can also use custom tags to route service requests to specific versions, which can help you with canary and blue-green deployments.

Consul compared to other DNS tools

Examples: NS1, AWS Route53, AzureDNS, Cloudflare DNS

Consul was originally designed as a centralized service registry for any cloud environment that dynamically tracks services as they are added, changed, or removed within a compute infrastructure. Consul maintains a catalog of these registered services and their attributes, such as IP addresses or service name. For more information, refer to What is Service Discovery?.

As a result, Consul can also provide basic DNS functionality, including lookups, alternate domains, and access controls. Since Consul is platform agnostic, you can retrieve service information across both cloud and on-premises data centers. Consul does not natively support some advanced DNS capabilities, such as filters or advanced routing logic. However, you can integrate Consul with existing DNS solutions, such as NS1 and DNSimple, to support these advanced capabilities.