diff --git a/app/assets/stylesheets/app.css.scss b/app/assets/stylesheets/app.css.scss
index e69de29bb..618b3c840 100644
--- a/app/assets/stylesheets/app.css.scss
+++ b/app/assets/stylesheets/app.css.scss
@@ -0,0 +1,3 @@
+.error-tab > a {
+  color: #a94442 !important;
+}
diff --git a/app/models/domain.rb b/app/models/domain.rb
index 18eb2dd9f..877b199f9 100644
--- a/app/models/domain.rb
+++ b/app/models/domain.rb
@@ -38,6 +38,9 @@ class Domain < ActiveRecord::Base
   validates :owner_contact, presence: true
 
   validate :validate_period
+  validate :validate_nameservers_count
+  validate :validate_nameservers_uniqueness, if: :new_record?
+  # validates_associated :nameservers
 
   attr_accessor :adding_admin_contact
   validate :validate_admin_contacts_max_count, if: :adding_admin_contact
@@ -55,7 +58,7 @@ class Domain < ActiveRecord::Base
   validate :validate_tech_contacts_max_count, if: :adding_tech_contact
 
   attr_accessor :deleting_tech_contact
-  # validate :validate_tech_contacts_min_count, if: :deleting_tech_contact
+  validate :validate_tech_contacts_min_count, if: :deleting_tech_contact
 
   def name=(value)
     value.strip!
@@ -111,6 +114,18 @@ class Domain < ActiveRecord::Base
     errors.add(:admin_contacts, :out_of_range) if admin_contacts_count.zero?
   end
 
+  def validate_nameservers_uniqueness
+    validated = []
+    nameservers.each do |ns|
+      next if ns.hostname.blank?
+      existing = nameservers.select { |x| x.hostname == ns.hostname }
+      next unless existing.length > 1
+      validated << ns.hostname
+      errors.add(:'nameservers.hostname', 'duplicate')
+      ns.errors.add(:hostname, :taken)
+    end
+  end
+
   def validate_period
     return unless period.present?
     if period_unit == 'd'
@@ -131,6 +146,10 @@ class Domain < ActiveRecord::Base
     errors.empty?
   end
 
+  def associations_valid?(name)
+    !errors.keys.any? { |x| x.match(/#{name.to_s}/) }
+  end
+
   ## SHARED
 
   def to_s
diff --git a/app/views/admin/domains/_form.haml b/app/views/admin/domains/_form.haml
index f5f665f03..370cb0935 100644
--- a/app/views/admin/domains/_form.haml
+++ b/app/views/admin/domains/_form.haml
@@ -1,23 +1,24 @@
 = form_for([:admin, @domain]) do |f|
-  - if @domain.errors.any?
-    - @domain.errors.each do |attr, err|
-      = err
-      %br
-  - if @domain.errors.any?
-    %hr
-
+  .row
+    .col-md-12
+      = render 'admin/shared/errors', object: f.object
+      - if f.object.errors.any?
+        %hr
   .row
     .col-md-12
       / Nav tabs
       %ul.nav.nav-tabs{:role => "tablist", id: 'tabs'}
         %li.active
-          %a{"data-toggle" => "tab", :href => "#general-tab", :role => "tab"} general-tab
-        %li
-          %a{"data-toggle" => "tab", :href => "#nameservers-tab", :role => "tab"} nameservers-tab
-        %li
-          %a{"data-toggle" => "tab", :href => "#contacts-tab", :role => "tab"} contacts-tab
-        %li
-          %a{"data-toggle" => "tab", :href => "#statuses-tab", :role => "tab"} statuses-tab
+          %a{"data-toggle" => "tab", :href => "#general-tab", :role => "tab"}= t('shared.general')
+        - li_class = @domain.associations_valid?(:nameservers) ? nil : 'error-tab'
+        %li{class: li_class}
+          %a{"data-toggle" => "tab", :href => "#nameservers-tab", :role => "tab"}= t('shared.nameservers')
+        - li_class = @domain.associations_valid?(:domain_contacts) ? nil : 'error-tab'
+        %li{class: li_class}
+          %a{"data-toggle" => "tab", :href => "#contacts-tab", :role => "tab"}= t('shared.contacts')
+        - li_class = @domain.associations_valid?(:domain_statuses) ? nil : 'error-tab'
+        %li{class: li_class}
+          %a{"data-toggle" => "tab", :href => "#statuses-tab", :role => "tab"}= t('shared.statuses')
       / Tab panes
       .tab-content{style:'margin-top: 20px;'}
         #general-tab.tab-pane.active
diff --git a/app/views/admin/domains/form_partials/_contacts.haml b/app/views/admin/domains/form_partials/_contacts.haml
index 3b9abefdd..341e68eac 100644
--- a/app/views/admin/domains/form_partials/_contacts.haml
+++ b/app/views/admin/domains/form_partials/_contacts.haml
@@ -7,6 +7,8 @@
       .panel-body
         .errors
           = render 'admin/shared/errors', object: contact_fields.object
+          - if contact_fields.object.errors.any?
+            %hr
         .row
           .col-md-6
             .form-group
diff --git a/app/views/admin/domains/form_partials/_nameservers.haml b/app/views/admin/domains/form_partials/_nameservers.haml
index 8ee314c9b..12770e2a9 100644
--- a/app/views/admin/domains/form_partials/_nameservers.haml
+++ b/app/views/admin/domains/form_partials/_nameservers.haml
@@ -7,6 +7,8 @@
       .panel-body
         .errors
           = render 'admin/shared/errors', object: ns_fields.object
+          - if ns_fields.object.errors.any?
+            %hr
         .row
           .col-md-12
             .form-group
@@ -28,5 +30,3 @@
       item.find('.errors').html('');
     }
   });
-
-
diff --git a/app/views/admin/domains/form_partials/_statuses.haml b/app/views/admin/domains/form_partials/_statuses.haml
index 79109e6ae..1d78704c2 100644
--- a/app/views/admin/domains/form_partials/_statuses.haml
+++ b/app/views/admin/domains/form_partials/_statuses.haml
@@ -7,6 +7,8 @@
       .panel-body
         .errors
           = render 'admin/shared/errors', object: status_fields.object
+          - if status_fields.object.errors.any?
+            %hr
         .row
           .col-md-6
             .form-group
diff --git a/app/views/admin/shared/_errors.haml b/app/views/admin/shared/_errors.haml
index 8873098bb..bcbdd7121 100644
--- a/app/views/admin/shared/_errors.haml
+++ b/app/views/admin/shared/_errors.haml
@@ -1,5 +1,6 @@
 - if object.errors.any?
   - object.errors.each do |attr, err|
+    - next if attr.match(/\./)
     - next if attr == :epp_errors
     = err
     %br