diff --git a/azure_test.go b/azure_test.go
new file mode 100644
index 00000000..49028a69
--- /dev/null
+++ b/azure_test.go
@@ -0,0 +1,47 @@
+package ipcat
+
+import (
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestAzure(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		fmt.Fprintln(w, `
+<?xml version="1.0" encoding="utf-8"?>
+<AzurePublicIpAddresses xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <Region Name="europewest">
+    <IpRange Subnet="40.112.124.0/24" />
+    <IpRange Subnet="65.52.128.0/19" />
+  </Region>
+  <Region Name="useast">
+    <IpRange Subnet="23.96.0.0/18" />
+    <IpRange Subnet="23.96.64.0/28" />
+  </Region>
+</AzurePublicIpAddresses>
+`)
+
+	}))
+
+	defer ts.Close()
+	msazure = ts.URL
+	b, err := DownloadAzure()
+	if err != nil {
+		t.Fatalf("DownloadAzure() error: %v", err)
+	}
+
+	ipset := NewIntervalSet(100)
+	err = UpdateAzure(ipset, b)
+	if err != nil {
+		t.Fatalf("UpdateAzure error: %v", err)
+	}
+	rec, err := ipset.Contains("23.96.0.0")
+	if err != nil {
+		t.Fatalf("ipset.Contains(%q) error: %v", "23.96.0.0", err)
+	}
+	if rec == nil {
+		t.Errorf("ipset.Contains(%q) rec = nil, want exists", "23.96.0.0")
+	}
+}