module huawei-bras-dhcp-server {

    yang-version 1;

    namespace
      "urn:huawei:yang:huawei-bras-dhcp-server";

    prefix bras-dhcp-server;

    import huawei-ifm {
      prefix ifm;
    }
    import huawei-network-instance {
      prefix ni;
    }
    import ietf-inet-types {
      prefix inet;
    }
    import huawei-extension {
      prefix ext;
    }
    import huawei-l3vpn {
      prefix l3vpn;
    }
    import ietf-yang-types {
      prefix yang;
    }

    organization
      "Huawei Technologies Co., Ltd.";

    contact
      "Huawei Industrial Base
Bantian, Longgang
Shenzhen 518129
People's Republic of China
Website: http://www.huawei.com
Email: support@huawei.com";

    description "Configure the DHCP server.";

    revision "2020-02-22" {
      description
        "Description modification.";
      reference
        "Huawei private.";

    }

    revision "2019-10-17" {
      description "Second revision.";
      reference
        "Huawei private.";

    }

    revision "2019-04-01" {
      description "Initial revision.";
      reference
        "Huawei private.";

    }

    ext:task-name "ippool";

    typedef dhcp-server-algorithm-type {
      type enumeration {
        enum "master-backup" {
          value 1;
          description
            "The master-backup algorithm.";
        }
        enum "loading-share" {
          value 2;
          description
            "The load sharing algorithm.";
        }
        enum "polling" {
          value 3;
          description
            "The polling algorithm.";
        }
      }
      description
        "DHCP server algorithm type.";
    }

    grouping server-property {
      description
        "Configure dhcp-server property.";
      leaf dead-count {
        type uint8 {
          range "1..64";
        }
        description
          "Specify the maximum number of times at which the DHCP server does not send response packets.";
      }

      leaf timeout {
        type uint8 {
          range "1..60";
        }
        units "s";
        default "25";
        description
          "Specify the timeout period for waiting for response packets from a DHCP server.";
      }

      leaf dead-time {
        type uint16 {
          range "1..65535";
        }
        units "min";
        default "3";
        description
          "Specify the recovery time of a DHCP server.";
      }

      leaf nak-count {
        type uint8 {
          range "0..255";
        }
        default "10";
        description
          "Specify the maximum number of NAK packets a DHCP server can receive consecutively.";
      }
    }  // grouping server-property

    container bras-dhcp-server {
      description
        "Configure the DHCP server.";
      container dhcp-servers {
        description
          "List of DHCP servers. A DHCP server must be bound to at least one dhcp-server group at the same time.";
        list dhcp-server {
          key "ip-address vpn-instance";
          description
            "Configure a DHCP server and must bind it to at least one dhcp-server group at the same time.";
          leaf ip-address {
            type inet:ipv4-address-no-zone;
            description
              "The IP address of the DHCP server.";
          }

          leaf vpn-instance {
            type leafref {
              path "/ni:network-instance/ni:instances/ni:instance/ni:name";
            }
            must
              "/ni:network-instance/ni:instances/ni:instance[ni:name=current()]/l3vpn:afs/l3vpn:af[l3vpn:type='ipv4-unicast']";
            description
              "Define the vpn-instance of a DHCP server. If dhcp-server belongs to the public network, vpn-instance can be defined as '_public_'.";
          }

          uses server-property;

          container statistics {
            config false;
            description
              "Display DHCPv4 server statistics.";
            leaf send-packets {
              type uint32;
              description
                "Number of sent packets.";
            }

            leaf receive-packets {
              type uint32;
              description
                "Number of received packets.";
            }

            leaf error-packets {
              type uint32;
              description
                "Number of error packets.";
            }

            leaf limit-number {
              type uint32;
              description
                "Number of packets discarded due to rate limiting.";
            }

            leaf timeout-packets {
              type uint32;
              description
                "Number of times that a DHCP server fails to respond to a DHCP request before the timer expires.";
            }

            leaf latest-send-time {
              type yang:date-and-time;
              description
                "Last time when a packet was sent.";
            }

            leaf lastest-receive-time {
              type yang:date-and-time;
              description
                "Last time when a packet was received.";
            }

            leaf discover-packets {
              type uint32;
              description
                "Number of discover messages.";
            }

            leaf request-packets {
              type uint32;
              description
                "Number of request messages.";
            }

            leaf decline-packets {
              type uint32;
              description
                "Number of decline messages.";
            }

            leaf release-packets {
              type uint32;
              description
                "Number of release messages.";
            }

            leaf inform-packets {
              type uint32;
              description
                "Number of inform messages.";
            }

            leaf offer-packets {
              type uint32;
              description
                "Number of offer messages.";
            }

            leaf ack-packets {
              type uint32;
              description
                "Number of ACK messages.";
            }

            leaf nak-packets {
              type uint32;
              description
                "Number of NAK messages.";
            }

            leaf bootp-requset-packets {
              type uint32;
              description
                "Number of BOOTP request packets.";
            }

            leaf bootp-ack-packets {
              type uint32;
              description
                "Number of BOOTP reply packets.";
            }

            leaf force-renew-packets {
              type uint32;
              description
                "Number of force renew packets.";
            }
          }  // container statistics

          container state {
            config false;
            description
              "Display DHCPv4 server state.";
            leaf status {
              type enumeration {
                enum "down" {
                  value 0;
                  description
                    "The down state of DHCPv4 bind server.";
                }
                enum "up" {
                  value 1;
                  description
                    "The up state of DHCPv4 bind server.";
                }
              }
              description
                "DHCPv4 server state.";
            }
          }  // container state
        }  // list dhcp-server
      }  // container dhcp-servers

      container dhcp-server-groups {
        description
          "List of DHCPv4 server groups.";
        list dhcp-server-group {
          key "name";
          max-elements 4096;
          description
            "Configure the DHCPv4 server group.";
          leaf name {
            ext:case-sensitivity "lower-only";
            type string {
              length "1..32";
              pattern '[a-z0-9._-]{1,32}';
            }
            must
              "../name != '-' and ../name != '--'";
            description
              "Specify the name of the DHCPv4 server group.";
          }

          leaf remote-backup-service-name {
            type string {
              length "1..32";
            }
            description
              "Specify the backup service associated with the DHCPv4 server group.";
          }

          container bind-servers {
            description
              "List of IP addresses of a DHCPv4 server and the weight of a specified DHCPv4 server when it performs load balancing.";
            list bind-server {
              key "ip-address vpn-instance";
              max-elements 8;
              description
                "Configure the IP address of a DHCPv4 server and the weight of a specified DHCPv4 server when it performs load balancing.";
              leaf ip-address {
                type leafref {
                  path "/bras-dhcp-server:bras-dhcp-server/bras-dhcp-server:dhcp-servers/bras-dhcp-server:dhcp-server/bras-dhcp-server:ip-address";
                }
                description
                  "Specify the IP address of the DHCPv4 server in the dotted decimal format.";
              }

              leaf vpn-instance {
                type leafref {
                  path "/bras-dhcp-server:bras-dhcp-server/bras-dhcp-server:dhcp-servers/bras-dhcp-server:dhcp-server/bras-dhcp-server:vpn-instance";
                }
                description
                  "Specify the VPN instance name. If the dhcp-server belongs to the public netwaork, vpn-instance can be defined as '_public_'.";
              }

              leaf weight {
                type uint32 {
                  range "0..100";
                }
                default "5";
                description
                  "Specify the weight of a DHCPv4 server.";
              }
            }  // list bind-server
          }  // container bind-servers

          container giaddr {
            must
              "not(./vpn-instance) or ./ip-address";
            description
              "Configure the giaddr address of packets sent by a DHCPv4 server group.";
            choice giaddr {
              description
                "Configure the giaddr address of packets sent by a DHCPv4 server group.";
              case if-name {
                description
                  "Specify the interface whose IP address that is used as the GiAddr address.";
                leaf if-name {
                  type leafref {
                    path "/ifm:ifm/ifm:interfaces/ifm:interface/ifm:name";
                  }
                  description
                    "Specify the interface whose IP address that is used as the GiAddr address of packets sent by the DHCPv4 server group.";
                }
              }  // case if-name

              case ip-address {
                description
                  "Specify the IP address that is used as the GiAddr address.";
                leaf ip-address {
                  type inet:ipv4-address-no-zone;
                  description
                    "Specify the IP address that is used as the GiAddr address of packets sent by the DHCPv4 server group. The address is in dotted decimal notation.";
                }

                leaf vpn-instance {
                  type leafref {
                    path "/ni:network-instance/ni:instances/ni:instance/ni:name";
                  }
                  must
                    "../vpn-instance!='_public_'";
                  must
                    "/ni:network-instance/ni:instances/ni:instance[ni:name=current()]/l3vpn:afs/l3vpn:af[l3vpn:type='ipv4-unicast']";
                  description
                    "Specify the VPN instance name.";
                }
              }  // case ip-address
            }  // choice giaddr

            leaf forward-rui-slave {
              when
                "../if-name or ../ip-address";
              type boolean;
              default "false";
              description
                "Enable/disable the slave device forwarding of RUI.";
            }
          }  // container giaddr

          container server-algorithm {
            description
              "Configure an algorithm of DHCPv4 servers.";
            leaf type {
              type dhcp-server-algorithm-type;
              default "master-backup";
              description
                "Specify the type of algorithm.";
            }

            leaf loose-check {
              when "../type = 'polling'";
              type boolean;
              default "false";
              description
                "Enable/disable DHCPv4 server algorithm as check-loose when algorithmType is polling.";
            }
          }  // container server-algorithm

          container server-forward {
            when
              "../server-algorithm/type = 'polling'";
            description
              "Configure the device to forward DHCP rebind messages to all DHCPv4 servers in a DHCPv4 server group.";
            leaf rebind-forward {
              type boolean;
              default "false";
              description
                "Enable/disable the device to forward DHCP rebind messages to all DHCPv4 servers in a DHCPv4 server group.";
            }
          }  // container server-forward

          container server-source {
            description
              "Configure the source IP address of the packets sent by a DHCPv4 server group.";
            choice config {
              description
                "Configure the source IP address of the packets sent by a DHCPv4 server group.";
              case gateway-mode {
                description
                  "Indicate the gateway address of the user address pool as source address.";
                leaf gateway-mode {
                  type empty;
                  description
                    "Indicate that the source address of the packets sent by the DHCPv4 server group is the gateway address of the user address pool.";
                }
              }  // case gateway-mode

              case if-name {
                description
                  "Indicate the IP address of the interface as the source address.";
                leaf if-name {
                  type leafref {
                    path "/ifm:ifm/ifm:interfaces/ifm:interface/ifm:name";
                  }
                  must
                    "/ifm:ifm/ifm:interfaces/ifm:interface[ifm:name=current()]/ifm:type='GigabitEthernet' or
/ifm:ifm/ifm:interfaces/ifm:interface[ifm:name=current()]/ifm:type='10GE' or
/ifm:ifm/ifm:interfaces/ifm:interface[ifm:name=current()]/ifm:type='XGigabitEthernet' or
/ifm:ifm/ifm:interfaces/ifm:interface[ifm:name=current()]/ifm:type='100GE' or
/ifm:ifm/ifm:interfaces/ifm:interface[ifm:name=current()]/ifm:type='400GE' or
/ifm:ifm/ifm:interfaces/ifm:interface[ifm:name=current()]/ifm:type='Virtual-Ethernet' or
/ifm:ifm/ifm:interfaces/ifm:interface[ifm:name=current()]/ifm:type='50GE' or
/ifm:ifm/ifm:interfaces/ifm:interface[ifm:name=current()]/ifm:type='50|100GE' or
/ifm:ifm/ifm:interfaces/ifm:interface[ifm:name=current()]/ifm:type='FlexE' or
/ifm:ifm/ifm:interfaces/ifm:interface[ifm:name=current()]/ifm:type='25GE' or
/ifm:ifm/ifm:interfaces/ifm:interface[ifm:name=current()]/ifm:type='Ethernet' or
/ifm:ifm/ifm:interfaces/ifm:interface[ifm:name=current()]/ifm:type='Eth-Trunk' or
/ifm:ifm/ifm:interfaces/ifm:interface[ifm:name=current()]/ifm:type='LoopBack'";
                  description
                    "Indicate that the source address of the packets sent by the DHCPv4 server group is the IP address of the interface.";
                }
              }  // case if-name
            }  // choice config
          }  // container server-source

          container release-agent {
            description
              "Configure the function of sending DHCPv4 release packets.";
            leaf enable {
              type boolean;
              default "true";
              description
                "Enable/disable the function of sending DHCPv4 release packets.";
            }
          }  // container release-agent
        }  // list dhcp-server-group
      }  // container dhcp-server-groups

      container server-global-property {
        description
          "Configure DHCP server global property.";
        uses server-property;
      }  // container server-global-property
    }  // container bras-dhcp-server
  }  // module huawei-bras-dhcp-server