diff --git a/test/models/nameserver/glue_record_test.rb b/test/models/nameserver/glue_record_test.rb
index 105138c8a..cec33ebf6 100644
--- a/test/models/nameserver/glue_record_test.rb
+++ b/test/models/nameserver/glue_record_test.rb
@@ -5,30 +5,41 @@ class NameserverGlueRecordTest < ActiveSupport::TestCase
     @nameserver = nameservers(:shop_ns1)
   end
 
-  def test_invalid_without_ip_if_glue_record_is_required
-    @nameserver.hostname = 'ns1.shop.test'
-    @nameserver.ipv4 = @nameserver.ipv6 = ''
-    assert @nameserver.invalid?
-    assert_includes @nameserver.errors.full_messages, 'Either IPv4 or IPv6 is required' \
+  def test_invalid_when_glue_record_is_required_and_no_ip_is_provided
+    domain = Domain.new(name: 'shop.test')
+    nameserver = Nameserver.new(domain: domain, hostname: 'ns1.shop.test')
+
+    assert nameserver.invalid?
+    assert_includes nameserver.errors.full_messages, 'Either IPv4 or IPv6 is required' \
     ' for glue record generation'
   end
 
-  def test_valid_with_ip_if_glue_record_is_required
-    @nameserver.hostname = 'ns1.shop.test'
-    @nameserver.ipv4 = ['192.0.2.1']
-    @nameserver.ipv6 = ''
-    assert @nameserver.valid?
+  def test_valid_when_glue_record_is_required_and_ipv4_is_provided
+    domain = Domain.new(name: 'shop.test')
+    nameserver = Nameserver.new(domain: domain, hostname: 'ns1.shop.test')
+    nameserver.ipv4 = ['192.0.2.1']
+
+    assert nameserver.valid?
   end
 
-  def test_valid_without_ip_if_glue_record_is_not_required
-    @nameserver.ipv4 = @nameserver.ipv6 = ''
-    assert @nameserver.valid?
+  def test_valid_when_glue_record_is_required_and_ipv6_is_provided
+    domain = Domain.new(name: 'shop.test')
+    nameserver = Nameserver.new(domain: domain, hostname: 'ns1.shop.test')
+    nameserver.ipv6 = ['2001:db8::1']
+
+    assert nameserver.valid?
   end
 
-  def test_valid_without_ip_when_glue_record_is_not_required
+  def test_valid_when_glue_record_is_not_required_and_no_ip_is_provided
+    domain = Domain.new(name: 'shop.test')
+    nameserver = Nameserver.new(domain: domain, hostname: 'ns1.registrar.test')
+
+    assert nameserver.valid?
+  end
+
+  def test_valid_when_glue_record_is_not_required_and_no_ip_is_provided_substring_match
     domain = Domain.new(name: 'le.test')
-    nameserver = Nameserver.new(domain: domain, hostname: 'ns1.example.test')
-    nameserver.ipv4 = nameserver.ipv6 = nil
+    nameserver = Nameserver.new(domain: domain, hostname: 'ns1.shop.test')
 
     assert nameserver.valid?
   end