diff --git a/specs/7.0/admin-network-on-bond.rst b/specs/7.0/admin-network-on-bond.rst
index 1be4f2b2..be762d89 100644
--- a/specs/7.0/admin-network-on-bond.rst
+++ b/specs/7.0/admin-network-on-bond.rst
@@ -20,7 +20,7 @@ In some cases user wants to bond admin interface. It is not possible
 for FUEL 6.0 and earlier release using UI. It is possible to bond admin
 interface via API and CLI, but in this case there is a problem with
 determining admin interface mac address during the provisioning stage.
-This is nailgun provisioning serializer issue. If admin interface was
+This is Nailgun provisioning serializer issue. If admin interface was
 bonded, serializer returns mac of the bond interface(empty value) and
 it breaks provisioning process.
 
@@ -30,7 +30,26 @@ Proposed change
 Nailgun provisioning serializer should be fixed to handle case when
 admin interface is bonded. Serializer may return first bonded slave
 interface mac address instead bond mac address. Lacp modes should
-be denied for admin interface via nailgun API(add validation rules).
+be denied for admin interface via Nailgun API(add validation rules).
+
+Additional `pxe` db field should be added into the nic interfaces db model
+to properly track initial admin interface(node's interface what was used for
+node's registering in Nailgun API). It necessary for identifying pxe
+interface if user decide to disassemble bond which includes admin interface.
+This property will be sent in registration request from Nailgun agent.
+Nailgun agent will identify `pxe` interface by:
+
+* ip address ( if some of node's interfaces IPs belong to the same network
+  as IP for Nailgun API which is taken from configuration file
+  "/etc/nailgun-agent/config.yaml")
+* mac address ( Nailgun agent does already have an ability to identify
+  interface which belongs to network with default gateway; it helps to
+  identify admin interface during the bootstrap stage ) in case if we are
+  using multiple node groups
+
+This property will be automatically calculated in the Nailgun(on the data from
+Nailgun agent) and user will not be able to change it.
+
 Possibility to bond admin interface via UI should be added. Available
 bond modes for admin interface in UI should be limited(only non-lacp modes).
 This limitation will be described in metadata which describes bonding
@@ -39,17 +58,17 @@ settings in following way::
       bonding:
           linux:
             mode:
-              - values: ["balance-rr", "active-backup", "802.3ad"]
+              - values: ["balance-rr", "active-backup"]
               - values: ["802.3ad"]
                 condition: "'experimental' in version:feature_groups or
-                            network:meta.unmovable == false"
+                            interface:pxe == false"
               - values: ["balance-xor", "broadcast", "balance-tlb",
                          "balance-alb"]
                 condition: "'experimental' in version:feature_groups"
 
-"network:meta.unmovable == false" condition indicates network what is not
-able to be bonded. This flag calculation will be based on network's
-property : 'unmovable'.
+"interface:pxe == false" condition indicates interfaces which are able to be
+bonded using lacp mode. This flag calculation will be based on interfaces's
+property : `pxe`.
 
 It is proposed to use only non-lacp bond modes for admin interface
 due to complex and unclear implementation in regarding to following reasons:
@@ -75,18 +94,41 @@ None
 Data model impact
 -----------------
 
-None
+Additional `pxe` boolean db field should be added into the node_nic_interfaces
+DB model.
 
 REST API impact
 ---------------
 
-Additional API validation rules should be added to prevent passing
-of lacp bond mode for admin interface.
+Additional API validation rules should be added to prevent passing of lacp
+bond mode for admin interface. Also API will be extended with rules preventing
+assignment of admin network to non-pxe interface.
 
 Upgrade impact
 --------------
 
-None
+Additional `pxe` field will be injected into nic interfaces db model and set
+to True for interfaces which belong to admin network during the database
+migration procedure.
+Also Nailgun server code will be fixed to properly calculate pxe interface
+in case if we have no `pxe` property set for any interface (to support old
+Nailgun agent versions). Calculation will be based on 'node.mac' property
+which is present in old agent's versions.
+Admin interface's bonding is not allowed for old releases, so metadata for
+old releases will be updated to not allow any bonding mode for `pxe`
+interface.
+
+Updated metadata example::
+
+      bonding:
+          linux:
+            mode:
+              - values: ["balance-rr", "active-backup", "802.3ad"]
+                condition: "interface:pxe == false"
+              - values: ["balance-xor", "broadcast", "balance-tlb",
+                         "balance-alb"]
+                condition: "interface:pxe == false and "
+                           "'experimental' in version:feature_groups and "
 
 Security impact
 ---------------
@@ -138,9 +180,13 @@ Work Items
 
 * Fix provisioning serializer to proper handle case when admin interface is
   bonded
-* Deny lacp modes for admin interface via nailgun API
+* Deny lacp modes for admin interface via Nailgun API
+* Deny to reassign admin network on non `pxe` interface via Nailgun API
 * Add possibility to bond admin interface via UI
 * Limit bond modes for admin interface via UI
+* Fix Nailgun to stick `pxe` property to admin interface during the bootstrap
+  stage
+* Fix Nailgun agent to calculate `pxe` property for interfaces
 
 Acceptance criteria
 -------------------