fix(azure): size snapshot forks as managed disks

steipete · steipete · commit b107bde654fe · 2026-05-30T16:44:53.000+01:00
diff --git a/internal/cli/azure.go b/internal/cli/azure.go
@@ -199,6 +199,9 @@ func azureVMSizeCandidatesForClass(class string) []string {
 func azureVMSizeCandidatesForConfig(cfg Config) []string {
 	candidates := azureVMSizeCandidatesForTargetModeArchitectureClass(cfg.TargetOS, cfg.WindowsMode, effectiveArchitectureForConfig(cfg), cfg.Class)
 	mode, err := NormalizeAzureOSDiskMode(cfg.AzureOSDisk)
+	if cfg.AzureSnapshot != "" {
+		mode = AzureOSDiskManaged
+	}
 	if err != nil || !azureOSDiskUsesFullCaching(mode) {
 		return candidates
 	}
diff --git a/worker/src/config.ts b/worker/src/config.ts
@@ -157,9 +157,18 @@ export function leaseConfig(input: LeaseRequest, defaults: LeaseConfigDefaults =
   }
   const machineClass = input.class ?? "beast";
   const azureOSDisk = normalizeAzureOSDiskMode(input.azureOSDisk ?? defaults.azureOSDisk);
+  const azureSnapshot = input.azureSnapshot ?? "";
+  const serverTypeAzureOSDisk = azureSnapshot ? "managed" : azureOSDisk;
   const serverType =
     input.serverType ??
-    serverTypeForConfig(provider, target, windowsMode, machineClass, architecture, azureOSDisk);
+    serverTypeForConfig(
+      provider,
+      target,
+      windowsMode,
+      machineClass,
+      architecture,
+      serverTypeAzureOSDisk,
+    );
   if (input.serverType) {
     validateArchitectureServerType(
       provider,
@@ -222,7 +231,7 @@ export function leaseConfig(input: LeaseRequest, defaults: LeaseConfigDefaults =
           ? (linuxOSImage?.azureArm64Image ?? "")
           : (linuxOSImage?.azureImage ?? "")
         : ""),
-    azureSnapshot: input.azureSnapshot ?? "",
+    azureSnapshot,
     azureOSDisk,
     gcpProject: input.gcpProject ?? "",
     gcpZone: input.gcpZone ?? "",
diff --git a/worker/test/config.test.ts b/worker/test/config.test.ts
@@ -381,6 +381,16 @@ describe("lease config", () => {
       sshPublicKey: "ssh-ed25519 test",
     });
     expect(windows.serverType).toBe("Standard_D8ads_v6");
+    const snapshot = leaseConfig({
+      provider: "azure",
+      target: "windows",
+      class: "standard",
+      azureSnapshot:
+        "/subscriptions/sub/resourceGroups/crabbox-leases/providers/Microsoft.Compute/snapshots/checkpoint-azure",
+      azureOSDisk: "ephemeral-preview",
+      sshPublicKey: "ssh-ed25519 test",
+    });
+    expect(snapshot.serverType).toBe("Standard_D2ads_v6");
   });
 
   it("uses AWS ARM defaults when requested", () => {
