[reconfigurator-planning] add test to ensure DNS lookups work on example system (#9233)

Ensure that DNS lookups for all internal services work on the example
system, through both the standard and qorb DNS resolvers.

I did notice that the example system doesn't set up every service.
Something worth doing in a followup, but this does catch issues like
(manually tested) the repo depot response being too large.

Author: sunshowers

Cargo.lock

@@ -14,6 +14,7 @@ omicron-workspace-hack.workspace = true
 omicron-uuid-kinds.workspace = true
 schemars.workspace = true
 serde.workspace = true
+strum.workspace = true
 
 [dev-dependencies]
 expectorate.workspace = true

internal-dns/types/Cargo.toml

@@ -5,6 +5,7 @@
 //! Well-known DNS names and related types for internal DNS (see RFD 248)
 
 use omicron_uuid_kinds::{OmicronZoneUuid, SledUuid};
+use strum::{EnumIter, IntoEnumIterator};
 
 /// Name for the special boundary NTP DNS name
 ///
@@ -32,7 +33,9 @@ pub const DNS_ZONE_EXTERNAL_TESTING: &str = "oxide-dev.test";
 pub const ZONE_APEX_NAME: &str = "@";
 
 /// Names of services within the control plane
-#[derive(Clone, Copy, Debug, Hash, Eq, Ord, PartialEq, PartialOrd)]
+#[derive(
+    Clone, Copy, Debug, Hash, Eq, Ord, PartialEq, PartialOrd, EnumIter,
+)]
 pub enum ServiceName {
     /// The HTTP interface to a single-node ClickHouse server.
     Clickhouse,
@@ -78,6 +81,16 @@ pub enum ServiceName {
 }
 
 impl ServiceName {
+    /// Returns an iterator over all service name variants.
+    ///
+    /// Service names with associated data, such as [`Self::SledAgent`] and
+    /// [`Self::Crucible`], will have default values associated with them. When
+    /// iterating over these service names, ensure that you provide the expected
+    /// values associated with them.
+    pub fn iter() -> impl Iterator<Item = Self> {
+        <Self as IntoEnumIterator>::iter()
+    }
+
     fn service_kind(&self) -> &'static str {
         match self {
             ServiceName::Clickhouse => "clickhouse",

internal-dns/types/src/names.rs

@@ -55,9 +55,12 @@ uuid.workspace = true
 omicron-workspace-hack.workspace = true
 
 [dev-dependencies]
+dns-server.workspace = true
 dropshot.workspace = true
 expectorate.workspace = true
 hex-literal.workspace = true
+hickory-resolver.workspace = true
+internal-dns-types.workspace = true
 maplit.workspace = true
 omicron-common = { workspace = true, features = ["testing"] }
 omicron-test-utils.workspace = true