module ietf-vrrp {

    yang-version 1.1;

    namespace
      "urn:ietf:params:xml:ns:yang:ietf-vrrp";

    prefix vrrp;

    import ietf-inet-types {
      prefix inet;
    }
    import ietf-yang-types {
      prefix yang;
    }
    import ietf-interfaces {
      prefix if;
    }
    import ietf-ip {
      prefix ip;
    }

    organization
      "IETF Routing Area Working Group (RTGWG)";

    contact
      "WG Web:   <https://datatracker.ietf.org/wg/rtgwg/>
     WG List:  <mailto:rtgwg@ietf.org>

     Editor:   Xufeng Liu
               <mailto:xufeng.liu.ietf@gmail.com>

     Editor:   Athanasios Kyparlis
               <mailto:Athanasios_Kyparlis@jabil.com>
     Editor:   Ravi Parikh
               <mailto:parikhr@vmware.com>

     Editor:   Acee Lindem
               <mailto:acee@cisco.com>

     Editor:   Mingui Zhang
               <mailto:zhangmingui@huawei.com>";

    description
      "This YANG module defines a model for managing Virtual Router
     Redundancy Protocol (VRRP) versions 2 and 3.

     Copyright (c) 2018 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject to
     the license terms contained in, the Simplified BSD License set
     forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (https://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC 8347; see the
     RFC itself for full legal notices.";

    revision "2018-03-13" {
      description "Initial revision.";
      reference
        "RFC 8347: A YANG Data Model for the Virtual Router Redundancy
        	  Protocol (VRRP)
         RFC 2787: Definitions of Managed Objects for the Virtual
        	  Router Redundancy Protocol
         RFC 3768: Virtual Router Redundancy Protocol (VRRP)
         RFC 5798: Virtual Router Redundancy Protocol (VRRP)
        	  Version 3 for IPv4 and IPv6
         RFC 6527: Definitions of Managed Objects for the Virtual
        	  Router Redundancy Protocol Version 3 (VRRPv3)";

    }


    feature validate-interval-errors {
      description
        "This feature indicates that the system validates that the
       advertisement interval from advertisement packets received
       is the same as the interval configured for the local
       VRRP router.";
    }

    feature validate-address-list-errors {
      description
        "This feature indicates that the system validates that
       the address list from received packets matches the
       locally configured list for the VRRP router.";
    }

    typedef new-master-reason-type {
      type enumeration {
        enum "not-master" {
          value 0;
          description
            "The virtual router has never transitioned to master
           state.";
        }
        enum "priority" {
          value 1;
          description "Priority was higher.";
        }
        enum "preempted" {
          value 2;
          description
            "The master was preempted.";
        }
        enum "no-response" {
          value 3;
          description
            "Previous master did not respond.";
        }
      }
      description
        "Indicates why the virtual router has transitioned to
       master state.";
    }

    identity vrrp-event-type {
      description
        "Indicates the type of a VRRP protocol event.";
    }

    identity vrrp-event-none {
      base vrrp-event-type;
      description
        "Indicates a non-meaningful event.";
    }

    identity vrrp-event-startup {
      base vrrp-event-type;
      description
        "Indicates that a VRRP router has initiated the protocol.";
    }

    identity vrrp-event-shutdown {
      base vrrp-event-type;
      description
        "Indicates that a VRRP router has closed down the protocol.";
    }

    identity vrrp-event-higher-priority-backup {
      base vrrp-event-type;
      description
        "Indicates that a backup router has a higher priority than
       the current master.";
    }

    identity vrrp-event-master-timeout {
      base vrrp-event-type;
      description
        "Indicates that the current master has not sent an
       advertisement within the limit of master-down-interval.";
    }

    identity vrrp-event-interface-up {
      base vrrp-event-type;
      description
        "Indicates that the VRRP-enabled interface has become
       'operational up'.";
    }

    identity vrrp-event-interface-down {
      base vrrp-event-type;
      description
        "Indicates that the VRRP-enabled interface has become
       'operational down'.";
    }

    identity vrrp-event-no-primary-ip-address {
      base vrrp-event-type;
      description
        "Indicates that the primary IP address on the VRRP-enabled
       interface has become unavailable.";
    }

    identity vrrp-event-primary-ip-address {
      base vrrp-event-type;
      description
        "Indicates that the primary IP address on the VRRP-enabled
       interface has become available.";
    }

    identity vrrp-event-no-virtual-ip-addresses {
      base vrrp-event-type;
      description
        "Indicates that there are no virtual IP addresses on the
       virtual router.";
    }

    identity vrrp-event-virtual-ip-addresses {
      base vrrp-event-type;
      description
        "Indicates that there are virtual IP addresses on the
       virtual router.";
    }

    identity vrrp-event-preempt-hold-timeout {
      base vrrp-event-type;
      description
        "Indicates that the configured preemption hold time has
       passed.";
    }

    identity vrrp-event-lower-priority-master {
      base vrrp-event-type;
      description
        "Indicates that there is a lower-priority VRRP master.";
    }

    identity vrrp-event-owner-preempt {
      base vrrp-event-type;
      description
        "Indicates that the owner has preempted another router to
       become the master.";
    }

    identity vrrp-error-global {
      description
        "Indicates the type of a VRRP error that occurred
       for a packet before it reaches a VRRP router.";
    }

    identity checksum-error {
      base vrrp-error-global;
      description
        "A packet has been received with an invalid VRRP checksum
       value.";
    }

    identity ip-ttl-error {
      base vrrp-error-global;
      description
        "A packet has been received with IP TTL (Time-To-Live)
       not equal to 255.";
    }

    identity version-error {
      base vrrp-error-global;
      description
        "A packet has been received with an unknown or unsupported
       version number.";
    }

    identity vrid-error {
      base vrrp-error-global;
      description
        "A packet has been received with a Virtual Router Identifier
       (VRID) that is not valid for any virtual router on this
       router.";
    }

    identity vrrp-error-virtual-router {
      description
        "Indicates the type of a VRRP error that occurred
       after a packet reaches a VRRP router.";
    }

    identity address-list-error {
      base vrrp-error-virtual-router;
      description
        "A packet has been received with an address list that
       does not match the locally configured address list for
       the virtual router.";
    }

    identity interval-error {
      base vrrp-error-virtual-router;
      description
        "A packet has been received with an advertisement interval
       different than the interval configured for the local
       virtual router.";
    }

    identity packet-length-error {
      base vrrp-error-virtual-router;
      description
        "A packet has been received with a packet length less
       than the length of the VRRP header.";
    }

    identity vrrp-state-type {
      description
        "Indicates the state of a virtual router.";
    }

    identity initialize {
      base vrrp-state-type;
      description
        "Indicates that the virtual router is waiting
       for a startup event.";
    }

    identity backup {
      base vrrp-state-type;
      description
        "Indicates that the virtual router is monitoring the
       availability of the master router.";
    }

    identity master {
      base vrrp-state-type;
      description
        "Indicates that the virtual router is forwarding
       packets for IP addresses that are associated with
       this virtual router.";
    }

    identity vrrp-version {
      description "The version of VRRP.";
    }

    identity vrrp-v2 {
      base vrrp-version;
      description
        "Indicates version 2 of VRRP.";
    }

    identity vrrp-v3 {
      base vrrp-version;
      description
        "Indicates version 3 of VRRP.";
    }

    container vrrp {
      config false;
      description
        "VRRP data at the global level.";
      leaf virtual-routers {
        type uint32;
        description
          "Number of configured virtual routers.";
      }

      leaf interfaces {
        type uint32;
        description
          "Number of interfaces with VRRP configured.";
      }

      container statistics {
        description
          "VRRP global statistics.";
        leaf discontinuity-datetime {
          type yang:date-and-time;
          description
            "The time on the most recent occasion at which any
one or more of checksum-errors, version-errors,
vrid-errors, or ip-ttl-errors suffered a
discontinuity.

If no such discontinuities have occurred since the last
re-initialization of the local management subsystem,
then this node contains the time that the local management
subsystem re-initialized itself.";
        }

        leaf checksum-errors {
          type yang:counter64;
          description
            "The total number of VRRP packets received with an invalid
VRRP checksum value.";
          reference
            "RFC 5798: Virtual Router Redundancy Protocol (VRRP)
            	  Version 3 for IPv4 and IPv6.  Section 5.2.8";

        }

        leaf version-errors {
          type yang:counter64;
          description
            "The total number of VRRP packets received with an unknown
or unsupported version number.";
          reference
            "RFC 5798: Virtual Router Redundancy Protocol (VRRP)
            	  Version 3 for IPv4 and IPv6.  Section 5.2.1";

        }

        leaf vrid-errors {
          type yang:counter64;
          description
            "The total number of VRRP packets received with a VRID that
is not valid for any virtual router on this router.";
          reference
            "RFC 5798: Virtual Router Redundancy Protocol (VRRP)
            	  Version 3 for IPv4 and IPv6.  Section 5.2.3";

        }

        leaf ip-ttl-errors {
          type yang:counter64;
          description
            "The total number of VRRP packets received by the
virtual router with IP TTL (IPv4) or Hop Limit (IPv6)
not equal to 255.";
          reference
            "RFC 5798: Virtual Router Redundancy Protocol (VRRP)
            	  Version 3 for IPv4 and IPv6.
            	  Sections 5.1.1.3 and 5.1.2.3";

        }
      }  // container statistics
    }  // container vrrp

    notification vrrp-new-master-event {
      description
        "Notification event for the election of a new VRRP master.";
      leaf master-ip-address {
        type inet:ip-address;
        mandatory true;
        description
          "IPv4 or IPv6 address of the new master.";
      }

      leaf new-master-reason {
        type new-master-reason-type;
        mandatory true;
        description
          "Indicates why the virtual router has transitioned to
         master state.";
      }
    }  // notification vrrp-new-master-event

    notification vrrp-protocol-error-event {
      description
        "Notification event for a VRRP protocol error.";
      leaf protocol-error-reason {
        type identityref {
          base vrrp:vrrp-error-global;
        }
        mandatory true;
        description
          "Indicates the reason for the protocol error.";
      }
    }  // notification vrrp-protocol-error-event

    notification vrrp-virtual-router-error-event {
      description
        "Notification event for an error that happened on a
       virtual router.";
      leaf interface {
        type if:interface-ref;
        mandatory true;
        description
          "Indicates the interface on which the event has occurred.";
      }

      choice ip-version {
        mandatory true;
        description
          "The error may have happened on either an IPv4 virtual
         router or an IPv6 virtual router.  The information
         related to a specific IP version is provided by one of
         the following cases.";
        case ipv4 {
          description "IPv4.";
          container ipv4 {
            description
              "Error information for IPv4.";
            leaf vrid {
              type leafref {
                path "/if:interfaces/if:interface[if:name = current()/../../vrrp:interface]/ip:ipv4/vrrp:vrrp/vrrp:vrrp-instance/vrrp:vrid";
              }
              mandatory true;
              description
                "Indicates the virtual router on which the event has
               occurred.";
            }
          }  // container ipv4
        }  // case ipv4

        case ipv6 {
          description "IPv6.";
          container ipv6 {
            description
              "Error information for IPv6.";
            leaf vrid {
              type leafref {
                path "/if:interfaces/if:interface[if:name = current()/../../vrrp:interface]/ip:ipv6/vrrp:vrrp/vrrp:vrrp-instance/vrrp:vrid";
              }
              mandatory true;
              description
                "Indicates the virtual router on which the event has
               occurred.";
            }
          }  // container ipv6
        }  // case ipv6
      }  // choice ip-version

      leaf virtual-router-error-reason {
        type identityref {
          base vrrp:vrrp-error-virtual-router;
        }
        mandatory true;
        description
          "Indicates the reason for the virtual router error.";
      }
    }  // notification vrrp-virtual-router-error-event
  }  // module ietf-vrrp