diff --git a/app/helpers/domains_helper.rb b/app/helpers/domains_helper.rb
index 597f46a..89db2fb 100644
--- a/app/helpers/domains_helper.rb
+++ b/app/helpers/domains_helper.rb
@@ -1,24 +1,25 @@
 module DomainsHelper
 
   # Human names for domain states
   def human_state(state)
     human = case state.to_sym
             when :initial then 'Initial'
             when :pending_install then 'Becoming public'
             when :pending_signing then 'Signing zone'
             when :wait_for_ready then 'Waiting for KSK to become ready'
             when :pending_ds then 'Publishing DS records'
+            when :pending_ds_rollover then 'Performing KSK rollover'
             when :pending_plain then 'Removing dnssec'
             when :pending_remove then 'Preparing removal'
             when :operational then 'Operational'
             when :destroy then 'Ready to be destroyed'
             else
               state
             end
 
     prog = Domain.dnssec_progress(state)
     return human if prog.nil?
 
     "#{human} (#{prog})"
   end
 end
diff --git a/app/models/domain.rb b/app/models/domain.rb
index 4ad9dd7..c841493 100644
--- a/app/models/domain.rb
+++ b/app/models/domain.rb
@@ -1,277 +1,284 @@
 class Domain < ActiveRecord::Base
   class NotAChild < StandardError; end
   self.inheritance_column = :nx
 
   # List all supported domain types.
   def self.domain_types
     [
       'NATIVE',
       'MASTER',
       'SLAVE',
     ]
   end
 
   # List domain types that can be created.
   def self.allowed_domain_types
     domain_types - WebDNS.settings[:prohibit_domain_types]
   end
 
   # List parent authorities
   def self.dnssec_parent_authorities
     WebDNS.settings[:dnssec_parent_authorities]
   end
 
   # Fire event after transaction commmit
   # Changing state inside a hook messes things up,
   # this trick handles that
   attr_accessor :fire_event
 
   belongs_to :group
   has_many :jobs
   has_many :records
   # BUG in bump_serial_trigger
   has_one :soa, -> { unscope(where: :type).where(type: 'soa') }, class_name: SOA
 
   validates :group_id, presence: true
   validates :name, uniqueness: true, presence: true
   validates :type, presence: true, inclusion: { in: domain_types }
   validates :master, presence: true, ipv4: true, if: :slave?
 
   validates :dnssec, inclusion: { in: [false] }, unless: :dnssec_elegible?
   validates :dnssec_parent_authority, inclusion: { in: dnssec_parent_authorities }, if: :dnssec?
   validates :dnssec_parent, hostname: true, if: :dnssec?
 
   after_create :generate_soa
   after_create :generate_ns
 
   after_create :install
   before_save :check_convert
   after_commit :after_commit_event
 
   attr_writer :serial_strategy
 
   def self.dnssec_progress(current_state)
     progress = [
       :pending_signing, # 1/3
       :wait_for_ready,  # 2/3
       :pending_ds]      # 3/3
     idx = progress.index(current_state.to_sym)
     return if idx.nil?
 
     [idx+1, progress.size].join('/')
   end
 
   state_machine initial: :initial do
     after_transition(any => :pending_install) { |domain, _t| Job.add_domain(domain) }
     after_transition(any => :pending_remove) { |domain, _t| Job.shutdown_domain(domain) }
     after_transition(any => :pending_signing) { |domain, _t| Job.dnssec_sign(domain) }
     after_transition(any => :wait_for_ready) { |domain, _t| Job.wait_for_ready(domain) }
     after_transition(any => :pending_ds) { |domain, t| Job.dnssec_push_ds(domain, *t.args) }
+    after_transition(any => :pending_ds_rollover) { |domain, t| Job.dnssec_push_ds(domain, *t.args) }
     after_transition(any => :pending_plain) { |domain, _t| Job.convert_to_plain(domain) }
     after_transition(any => :destroy) { |domain, _t| domain.destroy }
 
     # User events
     event :install do
       transition initial: :pending_install
     end
 
     event :dnssec_sign do
       transition operational: :pending_signing
     end
 
     event :signed do
       transition pending_signing: :wait_for_ready
     end
 
     event :push_ds do
-      # TODO: push_ds is triggered on multiple occasions
-      # operational: :operational
-      transition wait_for_ready: :pending_ds
+      transition wait_for_ready: :pending_ds, operational: :pending_ds_rollover
     end
 
     event :plain_convert do
       transition operational: :pending_plain
     end
 
     event :remove do
       transition operational: :pending_remove
     end
 
     # Machine events
     event :installed do
       transition pending_install: :operational
     end
 
     event :converted do
       transition [:pending_ds, :pending_plain] => :operational
     end
 
+    event :complete_rollover do
+      transition pending_ds_rollover: :operational
+    end
+
     event :cleaned_up do
       transition pending_remove: :destroy
     end
+
+    event :ksk_rollover_detected do
+      transition operational: :ksk_rollover
+    end
   end
 
   # Returns true if this domain is elegigble for DNSSEC
   def dnssec_elegible?
     return false if slave?
 
     true
   end
 
   # Get the zone's serial strategy.
   #
   # Returns one of the supported serial strategies.
   def serial_strategy
     @serial_strategy ||= WebDNS.settings[:serial_strategy]
   end
 
   # Returns true if this a reverse zone.
   def reverse?
     name.end_with?('.in-addr.arpa') || name.end_with?('.ip6.arpa')
   end
 
   # Returns true if this a ENUM zone.
   def enum?
     name.end_with?('.e164.arpa')
   end
 
   # Returns true if this is a slave zone.
   def slave?
     type == 'SLAVE'
   end
 
   # Compute subnet for reverse records
   def subnet
     return if not reverse?
 
     if name.end_with?('.in-addr.arpa')
       subnet_v4
     elsif name.end_with?('.ip6.arpa')
       subnet_v6
     end
   end
 
   def self.replace_ds(parent, child, records)
     parent = find_by_name!(parent)
     fail NotAChild if not child.end_with?(parent.name)
 
     existing = parent.records.where(name: child, type: 'DS')
     recs = records.map { |rec| DS.new(domain: parent, name: child, content: rec) }
 
     ActiveRecord::Base.transaction do
       existing.destroy_all
       recs.map(&:save!)
     end
   end
 
   # Apply bulk to operations to the zones
   #
   # 1) Deletions
   # 2) Changes
   # 3) Additions
   def bulk(opts)
     deletes = opts[:deletes] || []
     changes = opts[:changes] || {}
     additions = opts[:additions] || {}
     errors = Hash.new { |h, k| h[k] = {} }
 
     ActiveRecord::Base.transaction do
       # Deletes
       to_delete = records.where(id: deletes).index_by(&:id)
       deletes.each { |rec_id|
         if rec = to_delete[Integer(rec_id)]
           rec.destroy
           next
         end
 
         errors[:deletes][rec_id] = 'Deleted record not found'
       }
 
       # Changes
       to_change = records.where(id: changes.keys).index_by(&:id)
       changes.each {|rec_id, changes|
         binding
         if rec = to_change[Integer(rec_id)]
           errors[:changes][rec_id] = rec.errors.full_messages.join(', ') if !rec.update(changes)
           next
         end
 
         errors[:changes][rec_id] = 'Changed record not found'
       }
 
       # Additions
       additions.each { |inc, attrs|
         rec = records.new(attrs)
         errors[:additions][inc] = rec.errors.full_messages.join(', ') if !rec.save
       }
 
       raise ActiveRecord::Rollback if errors.any?
     end
 
     errors
   end
 
   private
 
   def subnet_v4
     # get ip octets (remove .in-addr.arpa)
     octets = name.split('.')[0...-2].reverse
     return if octets.any? { |_| false }
 
     mask = 8 * octets.size
     octets += [0, 0, 0, 0]
 
     ip = IPAddr.new octets[0, 4].join('.')
 
     [ip, mask].join('/')
   end
 
   def subnet_v6
     nibbles = name.split('.')[0...-2].reverse
     return if nibbles.any? { |_| false }
 
     mask = 4 * nibbles.size
     nibbles += [0] * 32
 
     ip = IPAddr.new nibbles[0, 32].in_groups_of(4).map(&:join).join(':')
 
     [ip, mask].join('/')
   end
 
   # Hooks
 
   def generate_soa
     soa_record = SOA.new(domain: self)
 
     soa_record.save!
   end
 
   def generate_ns
     return if slave?
     return if WebDNS.settings[:default_ns].empty?
 
     WebDNS.settings[:default_ns].each { |ns|
       Record.find_or_create_by!(domain: self, type: 'NS', name: '', content: ns)
     }
   end
 
   def check_convert
     return if !dnssec_changed?
 
     event = dnssec ? :dnssec_sign : :plain_convert
     if state_events.include?(event)
       self.fire_event = event # Schedule event for after commit
       return true
     end
 
     errors.add(:dnssec, 'You cannot modify dnssec settings in this state!')
     false
   end
 
   def after_commit_event
     return if !fire_event
 
     fire_state_event(fire_event)
     self.fire_event = nil
   end
 end
diff --git a/app/models/job.rb b/app/models/job.rb
index fc0db3c..74ba54e 100644
--- a/app/models/job.rb
+++ b/app/models/job.rb
@@ -1,89 +1,101 @@
 class Job < ActiveRecord::Base
   belongs_to :domain
 
   scope :pending, -> { where(status: 0) }
   scope :completed, -> { where(status: [1, 2]) }
 
   def failed?
     status == 2
   end
 
   def arguments
     JSON.parse(args)
   end
 
   class << self
     def add_domain(domain)
       ActiveRecord::Base.transaction do
         jobs_for_domain(domain, :add_domain)
 
         trigger_event(domain, :installed)
       end
     end
 
     def shutdown_domain(domain)
       ActiveRecord::Base.transaction do
         job_for_domain(domain, :remove_domain)
         job_for_domain(domain, :opendnssec_remove) if domain.dnssec?
 
         trigger_event(domain, :cleaned_up)
       end
     end
 
     def dnssec_sign(domain)
       ActiveRecord::Base.transaction do
         jobs_for_domain(domain,
                         :opendnssec_add,
                         :bind_convert_to_dnssec)
 
         trigger_event(domain, :signed)
       end
     end
 
     def wait_for_ready(domain)
       jobs_for_domain(domain,
                       :wait_for_ready_to_push_ds)
     end
 
     def dnssec_push_ds(domain, dss)
       opts = Hash[:dnssec_parent, domain.dnssec_parent,
                   :dnssec_parent_authority, domain.dnssec_parent_authority,
                   :dss, dss]
       ActiveRecord::Base.transaction do
         job_for_domain(domain, :publish_ds, opts)
         job_for_domain(domain, :wait_for_active)
 
         trigger_event(domain, :converted)
       end
     end
 
+    def dnssec_rollover_ds(domain, dss)
+      opts = Hash[:dnssec_parent, domain.dnssec_parent,
+                  :dnssec_parent_authority, domain.dnssec_parent_authority,
+                  :dss, dss]
+      ActiveRecord::Base.transaction do
+        job_for_domain(domain, :publish_ds, opts)
+        job_for_domain(domain, :wait_for_active)
+
+        trigger_event(domain, :complete_rollover)
+      end
+    end
+
     def convert_to_plain(domain)
       ActiveRecord::Base.transaction do
         jobs_for_domain(domain,
                         :remove_domain,
                         :add_domain,
                         :opendnssec_remove)
 
         trigger_event(domain, :converted)
       end
     end
 
     private
 
     def trigger_event(domain, event)
       job_for_domain(domain, :trigger_event, event: event)
     end
 
     def jobs_for_domain(domain, *job_names)
       job_names.each { |job_name| job_for_domain(domain, job_name) }
     end
 
     def job_for_domain(domain, job_name, args = {})
       args = { zone: domain.name }.merge!(args)
 
       create!(domain: domain, job_type: job_name, args: args.to_json)
     end
 
   end
 
 end
diff --git a/test/models/domain_test.rb b/test/models/domain_test.rb
index ef79d41..ec82793 100644
--- a/test/models/domain_test.rb
+++ b/test/models/domain_test.rb
@@ -1,220 +1,228 @@
 require 'test_helper'
 
 class DomainTest < ActiveSupport::TestCase
   def setup
     @domain = build(:domain)
   end
 
   test 'automatic SOA creation' do
     @domain.save!
     @domain.reload
     assert_not_nil @domain.soa
   end
 
   test 'increment serial on new record' do
     @domain.save!
     soa = @domain.soa
 
     assert_serial_update soa do
       www = A.new(name: 'www', domain: @domain, content: '1.2.3.4')
       www.save!
     end
   end
 
   test 'increment serial on record update' do
     @domain.save!
     www = A.new(name: 'www', domain: @domain, content: '1.2.3.4')
     www.save!
     soa = @domain.soa.reload
 
     assert_serial_update soa do
       www.content = '1.2.3.5'
       www.save!
     end
   end
 
   test 'automatic NS creation' do
     @domain.save!
     @domain.reload
     assert_equal WebDNS.settings[:default_ns].sort,
                  @domain.records.where(type: 'NS').pluck(:content).sort
   end
 
   test 'increment serial on record destroy' do
     @domain.save!
     www = A.new(name: 'www', domain: @domain, content: '1.2.3.4')
     www.save!
     soa = @domain.soa.reload
 
     assert_serial_update soa do
       www.destroy!
     end
   end
 
   class SlaveDomainTest < ActiveSupport::TestCase
     def setup
       @domain = build(:slave)
     end
 
     test 'saves' do
       @domain.save
 
       assert_empty @domain.errors
     end
 
     test 'automatic SOA creation' do
       @domain.save!
       @domain.reload
       assert_not_nil @domain.soa
       assert_equal 1, @domain.soa.serial
     end
 
     test 'validates master' do
       @domain.master = 'not-an-ip'
       @domain.save
 
       assert_not_empty @domain.errors['master']
     end
 
     test 'no records are allowed for users' do
       @domain.save!
       rec = build(:a, domain_id: @domain.id)
 
       assert_not rec.valid?
       assert_not_empty rec.errors[:type]
     end
   end
 
   class StatesDomainTest < ActiveSupport::TestCase
     def setup
       @domain = build(:domain)
     end
 
     test 'domain lifetime' do
       assert_equal 'initial', @domain.state
 
       # Create
       assert_jobs do
         @domain.save! # user triggered
         assert_equal 'pending_install', @domain.state
       end
       @domain.installed # job triggered
       assert_equal 'operational', @domain.state
 
       # Convert to dnssec (sign)
       assert_jobs do
         assert @domain.dnssec_sign # user triggered
         assert_equal 'pending_signing', @domain.state
       end
 
       assert_jobs do
         assert @domain.signed # job triggered
         assert_equal 'wait_for_ready', @domain.state
       end
 
       # Convert to dnssec (publish ds)
       assert_jobs do
-        assert @domain.push_ds([:dss1, :dss2]) # DS script triggered
+        assert @domain.push_ds([:dss1, :dss2]) # triggered by schedule-ds script
         assert_equal 'pending_ds', @domain.state
       end
       assert @domain.converted # job triggered
       assert_equal 'operational', @domain.state
 
+      # KSK rollover
+      assert_jobs do
+        assert @domain.push_ds([:dss3, :dss4]) # triggered by schedule-ds script
+        assert_equal 'pending_ds_rollover', @domain.state
+      end
+      assert @domain.complete_rollover # job triggered
+      assert_equal 'operational', @domain.state
+
       # Convert to plain
       assert_jobs do
         assert @domain.plain_convert # user triggered
         assert_equal 'pending_plain', @domain.state
       end
       assert @domain.converted # job triggered
       assert_equal 'operational', @domain.state
 
       # Remove
       assert_jobs do
         assert @domain.remove # user triggered
         assert_equal 'pending_remove', @domain.state
       end
       assert @domain.cleaned_up # job triggered
       assert_equal 'destroy', @domain.state
     end
   end
 
   class DsDomainTest < ActiveSupport::TestCase
     def setup
       @domain = create(:domain)
       @ds = [
         '31406 8 1 189968811e6eba862dd6c209f75623d8d9ed9142',
         '31406 8 2 f78cf3344f72137235098ecbbd08947c2c9001c7f6a085a17f518b5d8f6b916d',
       ]
       @child = "dnssec.#{@domain.name}"
       @extra = DS.create(domain: @domain, name: @child, content: 'other')
     end
 
     test 'add ds records' do
       Domain.replace_ds(@domain.name, @child, @ds)
       @extra.save! # Should be deleted
 
       assert_equal @ds.size, DS.where(name: "dnssec.#{@domain.name}").count
       @ds.each { |ds|
         assert_equal 1, DS.where(name: "dnssec.#{@domain.name}", content: ds).count
       }
     end
 
     test 'check if child is a valid subdomain' do
       assert_raise Domain::NotAChild do
         Domain.replace_ds(@domain.name, 'dnssec.example.net', @ds)
       end
     end
 
   end
 
   class BulkTest < ActiveSupport::TestCase
     def setup
       @domain = create(:domain)
       @a = create(:a, domain: @domain)
       @aaaa = create(:aaaa, domain: @domain)
       @new = build(:mx, domain: @domain)
 
     end
 
     def valid_changes
       @valid_changes ||= begin
                            {}.tap { |c|
                              c[:deletes] = [@a.id]
                              c[:changes] = { @aaaa.id => { content: '::42' }}
                              c[:additions] = { 1 => @new.as_bulky_json }
                            }
                          end
     end
 
     def invalid_changes
       @invalid_changes ||= begin
                              {}.tap { |c|
                                c[:deletes] = [Record.maximum(:id) + 1]
                                c[:changes] = { @aaaa.id => { content: '1.2.3.4' }}
                                c[:additions] = { 1 => @new.as_bulky_json.update(prio: -1) }
                              }
                            end
     end
 
     test 'apply changes not' do
       err = @domain.bulk invalid_changes
 
       assert_not_empty err
       assert_includes err[:deletes][Record.maximum(:id) + 1], 'record not found'
       assert_includes err[:changes][@aaaa.id], 'not a valid IPv6'
       assert_includes err[:additions][1], 'not a valid DNS priority'
     end
 
     test 'apply changes' do
       err = @domain.bulk valid_changes
 
       @domain.reload
       @aaaa.reload
 
       assert_empty err
       assert_empty @domain.records.where(id: @a.id)
       assert_equal '::42', @aaaa.content
       assert_equal 1, @domain.records.where(type: :mx).count
     end
   end
 end