Merge pull request #14679 from hashicorp/docs/improve-ent-dns-flexibility-oss

docs: all enterprise locality labels now optional

.changelog/14679.txt

@@ -0,0 +1,3 @@
+```release-note:improvement
+dns: **(Enterprise Only)** All enterprise locality labels are now optional in DNS lookups. For example, service lookups support the following format: <tag>.]<service>.service[.<namespace>.ns][.<partition>.ap][.<datacenter>.dc]<domain>`. 
+```

website/content/docs/agent/config/config-files.mdx

@@ -1344,13 +1344,12 @@ Valid time units are 'ns', 'us' (or 'µs'), 'ms', 's', 'm', 'h'."
     equivalent to "no max age". To get a fresh value from the cache use a very small value
     of `1ns` instead of 0.
 
-  - `prefer_namespace` ((#dns_prefer_namespace)) <EnterpriseAlert inline /> **Deprecated in
-    Consul 1.11. Use the [canonical DNS format](/docs/discovery/dns#namespaced-partitioned-services) instead.** -
-    When set to true, in a DNS query for a service, the label between the domain
-    and the `service` label will be treated as a namespace name instead of a datacenter.
-    When set to false, the default, the behavior will be the same as non-Enterprise
-    versions and will assume the label is the datacenter. See: [this section](/docs/discovery/dns#namespaced-services)
-    for more details.
+  - `prefer_namespace` ((#dns_prefer_namespace)) <EnterpriseAlert inline /> **Deprecated in Consul 1.11.
+    Use the [canonical DNS format for enterprise service lookups](/docs/discovery/dns#service-lookups-for-consul-enterprise) instead.** -
+    When set to `true`, in a DNS query for a service, a single label between the domain
+    and the `service` label is treated as a namespace name instead of a datacenter.
+    When set to `false`, the default, the behavior is the same as non-Enterprise
+    versions and treats the single label as the datacenter.
 
 - `domain` Equivalent to the [`-domain` command-line flag](/docs/agent/config/cli-flags#_domain).
 

website/content/docs/discovery/dns.mdx

@@ -186,13 +186,13 @@ foobar.node.dc1.consul. 0 IN  A 10.1.10.12
 Valid formats for RFC 2782 SRV lookups depend on
 whether you want to filter results based on a service tag:
 
-- No filtering on service tag
+- No filtering on service tag:
 
    ```text
   _<service>._tcp[.service][.<datacenter>].<domain>
   ```
 
-- Filtering on service tag specified in the RFC 2782 protocol field
+- Filtering on service tag specified in the RFC 2782 protocol field:
 
    ```text
   _<service>._<tag>[.service][.<datacenter>].<domain>
@@ -353,15 +353,8 @@ $ echo -n "20010db800010002cafe000000001337" | perl -ne 'printf join(":", unpack
 
 By default, all service lookups use the `default` namespace
 within the partition and datacenter of the Consul agent that received the DNS query.
-
-Use the following query format to specify a namespace, partition, and/or datacenter
-for all service lookup types except `.query`,
-including `.service`, `.connect`, `.virtual`, and `.ingress`.
-At least two of those three fields (`namespace`, `partition`, `datacenter`)
-must be specified.
-```text
-[<tag>.]<service>.service.<namespace>.ns.<partition>.ap.<datacenter>.dc.<domain>
-```
+To lookup services in another namespace, partition, and/or datacenter,
+use the [canonical format](#canonical-format).
 
 Consul server agents are in the `default` partition.
 If DNS queries are addressed to Consul server agents,
@@ -369,7 +362,37 @@ service lookups to non-`default` partitions must explicitly specify
 the partition of the target service.
 
 To lookup services imported from a cluster peer,
-use a [service virtual IP lookups for Consul Enterprise](#service-virtual-ip-lookups-for-consul-enterprise) instead.
+refer to [service virtual IP lookups for Consul Enterprise](#service-virtual-ip-lookups-for-consul-enterprise) instead.
+
+#### Canonical format
+
+Use the following query format to specify namespace, partition, and/or datacenter
+for `.service`, `.connect`, `.virtual`, and `.ingress` service lookup types.
+All three fields (`namespace`, `partition`, `datacenter`) are optional.
+```text
+[<tag>.]<service>.service[.<namespace>.ns][.<partition>.ap][.<datacenter>.dc]<domain>
+```
+
+#### Alternative formats for specifying namespace
+
+Though the [canonical format](#canonical-format) is recommended for readability,
+you can use the following query formats specify namespace but not partition:
+
+- Specify both namespace and datacenter:
+
+  ```text
+  [<tag>.]<service>.service.<namespace>.<datacenter>.<domain>
+  ```
+
+- **Deprecated in Consul 1.11:**
+  Specify namespace without a datacenter,
+  which requires that DNS queries are addressed to a Consul agent with
+  [`dns_config.prefer_namespace`](/docs/agent/config/config-files#dns_prefer_namespace)
+  set to `true`:
+
+   ```text
+  [<tag>.]<service>.service.<namespace>.<domain>
+  ```
 
 ### Prepared Query Lookups