physical_router_config.py

#
# Copyright (c) 2014 Juniper Networks, Inc. All rights reserved.
#

"""
This file contains implementation of inetconf interface for physical router
configuration manager
"""

from lxml import etree
from ncclient import manager
import copy
import time
import datetime

class PhysicalRouterConfig(object):
    # mapping from contrail family names to junos
    _FAMILY_MAP = {
        'route-target': '<route-target/>',
        'inet-vpn': '<inet-vpn><unicast/></inet-vpn>',
        'inet6-vpn': '<inet6-vpn><unicast/></inet6-vpn>',
        'e-vpn': '<evpn><signaling/></evpn>'
    }

    def __init__(self, management_ip, user_creds, vendor, product, vnc_managed, logger=None):
        self.management_ip = management_ip
        self.user_creds = user_creds
        self.vendor = vendor
        self.product = product
        self.vnc_managed = vnc_managed
        self.reset_bgp_config()
        self._logger = logger
        self.commit_stats = {   
                                'netconf_enabled':False,
                                'netconf_enabled_status':'',
                                'last_commit_time': '',
                                'last_commit_duration': '',
                                'commit_status_message': '',
                                'total_commits_sent_since_up': 0,
                            }
        self.bgp_config_sent = False
    # end __init__

    def update(self, management_ip, user_creds, vendor, product, vnc_managed):
        self.management_ip = management_ip
        self.user_creds = user_creds
        self.vendor = vendor
        self.product = product
        self.vnc_managed = vnc_managed
    # end update

    def get_commit_stats(self):
        return self.commit_stats
    #end get_commit_stats

    def send_netconf(self, new_config, default_operation="merge",
                     operation="replace"):
        if (self.vendor is None or self.product is None or
               self.vendor.lower() != "juniper" or self.product.lower() != "mx"):
            self._logger.info("auto configuraion of physical router is not supported \
                on the configured vendor family, ip: %s, not pushing netconf message" % (self.management_ip))
            self.commit_stats['netconf_enabled'] = False
            self.commit_stats['netconf_enabled_status'] = "netconf configuraion is not supported on this vendor/product family"
            return
        if (self.vnc_managed is None or self.vnc_managed == False):
            self._logger.info("vnc managed property must be set for a physical router to get auto \
                configured, ip: %s, not pushing netconf message" % (self.management_ip))
            self.commit_stats['netconf_enabled'] = False
            self.commit_stats['netconf_enabled_status'] = "netconf auto configuraion is not enabled on this physical router"
            return
        self.commit_stats['netconf_enabled'] = True
        self.commit_stats['netconf_enabled_status'] = ''
        start_time = None
        try:
            with manager.connect(host=self.management_ip, port=22,
                                 username=self.user_creds['username'],
                                 password=self.user_creds['password'],
                                 unknown_host_cb=lambda x, y: True) as m:
                add_config = etree.Element(
                    "config",
                    nsmap={"xc": "urn:ietf:params:xml:ns:netconf:base:1.0"})
                config = etree.SubElement(add_config, "configuration")
                config_group = etree.SubElement(config, "groups", operation=operation)
                contrail_group = etree.SubElement(config_group, "name")
                contrail_group.text = "__contrail__"
                if isinstance(new_config, list):
                    for nc in new_config:
                        config_group.append(nc)
                else:
                    config_group.append(new_config)
                if operation == "delete":
                    apply_groups = etree.SubElement(config, "apply-groups", operation=operation)
                else:
                    apply_groups = etree.SubElement(config, "apply-groups")
                apply_groups.text = "__contrail__"
                self._logger.info("\nsend netconf message: %s\n" % (etree.tostring(add_config, pretty_print=True)))
                m.edit_config(
                    target='candidate', config=etree.tostring(add_config),
                    test_option='test-then-set',
                    default_operation=default_operation)
                self.commit_stats['total_commits_sent_since_up'] += 1
                start_time = time.time()
                m.commit()
                end_time = time.time()
                self.commit_stats['commit_status_message'] = 'success'
                self.commit_stats['last_commit_time'] = datetime.datetime.fromtimestamp(end_time).strftime('%Y-%m-%d %H:%M:%S')
                self.commit_stats['last_commit_duration'] = str(end_time - start_time)
        except Exception as e:
            if self._logger:
                self._logger.error("Router %s: %s" % (self.management_ip,
                                                      e.message))
                self.commit_stats['commit_status_message'] = 'failed to apply config, router response: ' + e.message
                if start_time is not None:
                    self.commit_stats['last_commit_time'] = datetime.datetime.fromtimestamp(start_time).strftime('%Y-%m-%d %H:%M:%S')
                    self.commit_stats['last_commit_duration'] = str(time.time() - start_time)
    # end send_config

    def add_dynamic_tunnels(self, tunnel_source_ip, ip_fabric_nets, bgp_router_ips):
        self.tunnel_config = etree.Element("routing-options")
        dynamic_tunnels = etree.SubElement(self.tunnel_config, "dynamic-tunnels")
        dynamic_tunnel = etree.SubElement(dynamic_tunnels, "dynamic-tunnel")
        etree.SubElement(dynamic_tunnel, "name").text = "__contrail__"
        etree.SubElement(dynamic_tunnel, "source-address").text = tunnel_source_ip
        etree.SubElement(dynamic_tunnel, "gre")
        if ip_fabric_nets is not None:
            for subnet in ip_fabric_nets.get("subnet", []): 
                dest_network = etree.SubElement(dynamic_tunnel, "destination-networks")
                etree.SubElement(dest_network, "name").text = subnet['ip_prefix'] + '/' + str(subnet['ip_prefix_len']) 
        for bgp_router_ip in bgp_router_ips:
            dest_network = etree.SubElement(dynamic_tunnel, "destination-networks")
            etree.SubElement(dest_network, "name").text = bgp_router_ip + '/32'
    #end add_dynamic_tunnels

    '''
     ri_name: routing instance name to be configured on mx
     import/export targets: routing instance import, export targets
     prefixes: for l3 public vrf static routes, bug#1395938 
     gateways: for l2 evpn, bug#1395944 
     router_external: this indicates the routing instance configured is for 
                      the public network
     interfaces: logical interfaces to be part of vrf
     fip_map: contrail instance ip to floating-ip map, used for snat & floating ip support
     private_vni: This is used only for configuring snat vrf.
                  private vn routing instance has an irb interface with the unit number 
                  same as network vni. Snat vrf firewall filter should be applied 
                  to private network irb interface, hence needed irb interface unit number. 
                  This allows the traffic flow from private vrf to snat to 
                  public and vice-versa
    '''
    def add_routing_instance(self, ri_name, import_targets, export_targets,
                             prefixes=[], gateways=[], router_external=False, 
                             interfaces=[], vni=None, fip_map=None, private_vni=None):
        self.routing_instances[ri_name] = {'import_targets': import_targets,
                                        'export_targets': export_targets,
                                        'prefixes': prefixes,
                                        'gateways': gateways,
                                        'router_external': router_external,
                                        'interfaces': interfaces,
                                        'vni': vni,
                                        'fip_map': fip_map}

        ri_config = self.ri_config or etree.Element("routing-instances")
        policy_config = self.policy_config or etree.Element("policy-options")
        ri = etree.SubElement(ri_config, "instance")
        etree.SubElement(ri, "name").text = ri_name
        ri_opt = None
        if router_external:
            ri_opt = etree.SubElement(ri, "routing-options")
            static_config = etree.SubElement(ri_opt, "static")
            route_config = etree.SubElement(static_config, "route")
            etree.SubElement(route_config, "name").text = "0.0.0.0/0"
            etree.SubElement(route_config, "next-table").text = "inet.0"

        #for both l2 and l3
        etree.SubElement(ri, "vrf-import").text = ri_name + "-import"
        etree.SubElement(ri, "vrf-export").text = ri_name + "-export"

        if vni is None or router_external:
            etree.SubElement(ri, "instance-type").text = "vrf"
            etree.SubElement(ri, "vrf-table-label")  #only for l3
            if fip_map is None:
                for interface in interfaces:
                    if_element = etree.SubElement(ri, "interface")
                    etree.SubElement(if_element, "name").text = interface

            if ri_opt is None:
                ri_opt = etree.SubElement(ri, "routing-options")
            if prefixes and fip_map is None:
                static_config = etree.SubElement(ri_opt, "static")
                for prefix in prefixes:
                    route_config = etree.SubElement(static_config, "route")
                    etree.SubElement(route_config, "name").text = prefix
                    etree.SubElement(route_config, "discard")
            auto_export = "<auto-export><family><inet><unicast/></inet></family></auto-export>"
            ri_opt.append(etree.fromstring(auto_export))
        else:
            etree.SubElement(ri, "instance-type").text = "virtual-switch"

        if fip_map is not None:
            if ri_opt is None:
                ri_opt = etree.SubElement(ri, "routing-options")
            static_config = etree.SubElement(ri_opt, "static")
            route_config = etree.SubElement(static_config, "route")
            etree.SubElement(route_config, "name").text = "0.0.0.0/0"
            etree.SubElement(route_config, "next-hop").text = interfaces[0]
            if_element = etree.SubElement(ri, "interface")
            etree.SubElement(if_element, "name").text = interfaces[0]
            public_vrf_ips = {}
            for pip in fip_map.values():
                if pip["vrf_name"] not in public_vrf_ips:
                    public_vrf_ips[pip["vrf_name"]] = set()
                public_vrf_ips[pip["vrf_name"]].add(pip["floating_ip"])

            for public_vrf, fips in public_vrf_ips.items():
                ri_public = etree.SubElement(ri_config, "instance")
                etree.SubElement(ri_public, "name").text = public_vrf
                ri_opt = etree.SubElement(ri_public, "routing-options")
                static_config = etree.SubElement(ri_opt, "static")
                if_element = etree.SubElement(ri_public, "interface")
                etree.SubElement(if_element, "name").text = interfaces[1]

                for fip in fips:
                    route_config = etree.SubElement(static_config, "route")
                    etree.SubElement(route_config, "name").text = fip + "/32"
                    etree.SubElement(route_config, "next-hop").text = interfaces[1]

        # add policies for export route targets
        ps = etree.SubElement(policy_config, "policy-statement")
        etree.SubElement(ps, "name").text = ri_name + "-export"
        term = etree.SubElement(ps, "term")
        etree.SubElement(term, "name").text= "t1"
        then = etree.SubElement(term, "then")
        for route_target in export_targets:
            comm = etree.SubElement(then, "community")
            etree.SubElement(comm, "add")
            etree.SubElement(comm, "community-name").text = route_target.replace(':', '_') 
        if fip_map is not None:
            #for nat instance
            etree.SubElement(then, "reject")
        else:
            etree.SubElement(then, "accept")

        # add policies for import route targets
        ps = etree.SubElement(policy_config, "policy-statement")
        etree.SubElement(ps, "name").text = ri_name + "-import"
        term = etree.SubElement(ps, "term")
        etree.SubElement(term, "name").text= "t1"
        from_ = etree.SubElement(term, "from")
        for route_target in import_targets:
            target_name = route_target.replace(':', '_')
            etree.SubElement(from_, "community").text = target_name
        then = etree.SubElement(term, "then")
        etree.SubElement(then, "accept")
        then = etree.SubElement(ps, "then")
        etree.SubElement(then, "reject")

        # add firewall config for public VRF
        forwarding_options_config = self.forwarding_options_config
        firewall_config = self.firewall_config
        if router_external:
            if self.forwarding_options_config is None:
                forwarding_options_config = etree.Element("forwarding-options")
                fo = etree.SubElement(forwarding_options_config, "family")
                inet  = etree.SubElement(fo, "inet")
                f = etree.SubElement(inet, "filter")
                etree.SubElement(f, "input").text = "redirect_to_public_vrf_filter"
                firewall_config = self.firewall_config or etree.Element("firewall")
                fc = etree.SubElement(firewall_config, "family")
                inet  = etree.SubElement(fc, "inet")
                f = etree.SubElement(inet, "filter")
                etree.SubElement(f, "name").text = "redirect_to_public_vrf_filter"
                self.inet_forwarding_filter = f
                term = etree.SubElement(f, "term")
                etree.SubElement(term, "name").text= "default-term"
                then_ = etree.SubElement(term, "then")
                etree.SubElement(then_, "accept")

            term = etree.Element("term")
            etree.SubElement(term, "name").text= "term-" + ri_name[:59]
            if prefixes:
                from_ = etree.SubElement(term, "from")
                etree.SubElement(from_, "destination-address").text = ';'.join(prefixes)
            then_ = etree.SubElement(term, "then")
            etree.SubElement(then_, "routing-instance").text = ri_name
            #insert after 'name' element but before the last term
            self.inet_forwarding_filter.insert(1, term) 

        if fip_map is not None:
            firewall_config = self.firewall_config or etree.Element("firewall")
            fc = etree.SubElement(firewall_config, "family")
            inet  = etree.SubElement(fc, "inet")
            f = etree.SubElement(inet, "filter")
            etree.SubElement(f, "name").text = "redirect_to_" + ri_name[:46] + "_vrf"
            term = etree.SubElement(f, "term")
            etree.SubElement(term, "name").text= "term-" + ri_name[:59]
            from_ = etree.SubElement(term, "from")
            for fip_user_ip in fip_map.keys():
                etree.SubElement(from_, "source-address").text = fip_user_ip
            then_ = etree.SubElement(term, "then")
            etree.SubElement(then_, "routing-instance").text = ri_name
            term = etree.SubElement(f, "term")
            etree.SubElement(term, "name").text= "default-term"
            then_ = etree.SubElement(term, "then")
            etree.SubElement(then_, "accept")

            interfaces_config = self.interfaces_config or etree.Element("interfaces")
            irb_intf = etree.SubElement(interfaces_config, "interface")
            etree.SubElement(irb_intf, "name").text = "irb"
            intf_unit = etree.SubElement(irb_intf, "unit")
            etree.SubElement(intf_unit, "name").text = str(private_vni)
            family = etree.SubElement(intf_unit, "family")
            inet = etree.SubElement(family, "inet")
            f = etree.SubElement(inet, "filter")
            iput = etree.SubElement(f, "input")
            etree.SubElement(iput, "filter-name").text = "redirect_to_" + ri_name[:46] + "_vrf"
              
        # add L2 EVPN and BD config
        bd_config = None
        interfaces_config = self.interfaces_config
        proto_config = self.proto_config
        if (router_external==False and vni is not None and 
                self.is_family_configured(self.bgp_params, "e-vpn")):
            etree.SubElement(ri, "vtep-source-interface").text = "lo0.0"
            bd_config = etree.SubElement(ri, "bridge-domains")
            bd= etree.SubElement(bd_config, "domain")
            etree.SubElement(bd, "name").text = "bd-" + str(vni)
            etree.SubElement(bd, "vlan-id").text = 'none'
            vxlan = etree.SubElement(bd, "vxlan")
            etree.SubElement(vxlan, "vni").text = str(vni)
            for interface in interfaces:
                if_element = etree.SubElement(bd, "interface")
                etree.SubElement(if_element, "name").text = interface
            etree.SubElement(bd, "routing-interface").text = "irb." + str(vni) #vni is unique, hence irb
            evpn_proto_config = etree.SubElement(ri, "protocols")
            evpn = etree.SubElement(evpn_proto_config, "evpn")
            etree.SubElement(evpn, "encapsulation").text = "vxlan"
            etree.SubElement(evpn, "extended-vni-list").text = "all"

            interfaces_config = self.interfaces_config or etree.Element("interfaces")
            irb_intf = etree.SubElement(interfaces_config, "interface")
            etree.SubElement(irb_intf, "name").text = "irb"
            etree.SubElement(irb_intf, "gratuitous-arp-reply")
            if gateways is not None:
                intf_unit = etree.SubElement(irb_intf, "unit")
                etree.SubElement(intf_unit, "name").text = str(vni)
                family = etree.SubElement(intf_unit, "family")
                inet = etree.SubElement(family, "inet")
                for gateway in gateways:
                    addr = etree.SubElement(inet, "address")
                    etree.SubElement(addr, "name").text = gateway + "/24"

            lo_intf = etree.SubElement(interfaces_config, "interface")
            etree.SubElement(lo_intf, "name").text = "lo0"
            intf_unit = etree.SubElement(lo_intf, "unit")
            etree.SubElement(intf_unit, "name").text = "0"
            family = etree.SubElement(intf_unit, "family")
            inet = etree.SubElement(family, "inet")
            addr = etree.SubElement(inet, "address")
            etree.SubElement(addr, "name").text = self.bgp_params['address'] + "/32"
            etree.SubElement(addr, "primary")
            etree.SubElement(addr, "preferred")

            for interface in interfaces:
                intf = etree.SubElement(interfaces_config, "interface")
                intfparts = interface.split(".")
                etree.SubElement(intf, "name").text = intfparts[0] 
                etree.SubElement(intf, "encapsulation").text = "ethernet-bridge" 
                intf_unit = etree.SubElement(intf, "unit")
                etree.SubElement(intf_unit, "name").text = intfparts[1]
                family = etree.SubElement(intf_unit, "family")
                etree.SubElement(family, "bridge")

            proto_config = self.proto_config or etree.Element("protocols")
            mpls = etree.SubElement(proto_config, "mpls")
            intf = etree.SubElement(mpls, "interface")
            etree.SubElement(intf, "name").text = "all"
        #fip services config
        services_config = self.services_config
        if fip_map is not None:
            services_config = self.services_config or etree.Element("services")
            service_name = 'sv-' + ri_name
            #mx has limitation for service-set and nat-rule name length, allowed max 63 chars
            service_name = service_name[:23]
            service_set = etree.SubElement(services_config, "service-set")
            etree.SubElement(service_set, "name").text = service_name
            nat_rule = etree.SubElement(service_set, "nat-rules")
            etree.SubElement(nat_rule, "name").text = service_name + "-sn-rule"
            nat_rule = etree.SubElement(service_set, "nat-rules")
            etree.SubElement(nat_rule, "name").text = service_name + "-dn-rule"
            next_hop_service = etree.SubElement(service_set, "next-hop-service")
            etree.SubElement(next_hop_service , "inside-service-interface").text = interfaces[0]
            etree.SubElement(next_hop_service , "outside-service-interface").text = interfaces[1]

            nat = etree.SubElement(services_config, "nat")
            snat_rule = etree.SubElement(nat, "rule")
            etree.SubElement(snat_rule, "name").text = service_name + "-sn-rule"
            etree.SubElement(snat_rule, "match-direction").text = "input"
            dnat_rule = etree.SubElement(nat, "rule")
            etree.SubElement(dnat_rule, "name").text = service_name + "-dn-rule"
            etree.SubElement(dnat_rule, "match-direction").text = "output"

            for pip, fip_vn in fip_map.items():
                fip = fip_vn["floating_ip"]
                term = etree.SubElement(snat_rule, "term")
                etree.SubElement(term, "name").text = "term_" + pip.replace('.', '_')
                from_ = etree.SubElement(term, "from")
                src_addr = etree.SubElement(from_, "source-address")
                etree.SubElement(src_addr, "name").text = pip + "/32"  # private ip
                then_ = etree.SubElement(term, "then")
                translated = etree.SubElement(then_, "translated")
                etree.SubElement(translated , "source-prefix").text = fip + "/32" # public ip
                translation_type = etree.SubElement(translated, "translation-type")
                etree.SubElement(translation_type, "basic-nat44")

                term = etree.SubElement(dnat_rule, "term")
                etree.SubElement(term, "name").text = "term_" + fip.replace('.', '_')
                from_ = etree.SubElement(term, "from")
                src_addr = etree.SubElement(from_, "destination-address")
                etree.SubElement(src_addr, "name").text = fip + "/32" #public ip
                then_ = etree.SubElement(term, "then")
                translated = etree.SubElement(then_, "translated")
                etree.SubElement(translated , "destination-prefix").text = pip + "/32" #source ip
                translation_type = etree.SubElement(translated, "translation-type")
                etree.SubElement(translation_type, "dnat-44")

            interfaces_config = self.interfaces_config or etree.Element("interfaces")
            si_intf = etree.SubElement(interfaces_config, "interface")
            intfparts = interfaces[0].split(".")
            etree.SubElement(si_intf, "name").text = intfparts[0]
            intf_unit = etree.SubElement(si_intf, "unit")
            etree.SubElement(intf_unit, "name").text = interfaces[0].split(".")[1]
            family = etree.SubElement(intf_unit, "family")
            etree.SubElement(family, "inet")
            etree.SubElement(intf_unit, "service-domain").text = "inside"
            intf_unit = etree.SubElement(si_intf, "unit")
            etree.SubElement(intf_unit, "name").text = interfaces[1].split(".")[1]
            family = etree.SubElement(intf_unit, "family")
            etree.SubElement(family, "inet")
            etree.SubElement(intf_unit, "service-domain").text = "outside"

        self.forwarding_options_config = forwarding_options_config
        self.firewall_config = firewall_config
        self.policy_config = policy_config
        self.proto_config = proto_config
        self.interfaces_config = interfaces_config
        self.services_config = services_config
        self.route_targets |= import_targets | export_targets
        self.ri_config = ri_config
    # end add_routing_instance

    def set_global_routing_options(self, bgp_params):
        if bgp_params['address'] is not None:
            self.global_routing_options_config = etree.Element("routing-options")
            etree.SubElement(self.global_routing_options_config, "router-id").text = bgp_params['address']
    #end set_global_routing_options

    def is_family_configured(self, params, family_name):
        if params is None or params.get('address_families') is None:
            return False
        families = params['address_families'].get('family', [])
        if family_name in families:
            return True
        return False

    def _add_family_etree(self, parent, params):
        if params.get('address_families') is None:
            return
        family_etree = etree.SubElement(parent, "family")
        for family in params['address_families'].get('family', []):
            if family in self._FAMILY_MAP:
                family_subtree = etree.fromstring(self._FAMILY_MAP[family])
                family_etree.append(family_subtree)
            else:
                etree.SubElement(family_etree, family)
    # end _add_family_etree

    def add_bgp_auth_config(self, bgp_config, bgp_params):
        if bgp_params.get('auth_data') is None:
            return
        keys = bgp_params['auth_data'].get('key_items', [])
        if len(keys) > 0:
            etree.SubElement(bgp_config, "authentication-key").text = keys[0].get('key')

    def add_bgp_hold_time_config(self, bgp_config, bgp_params):
        if bgp_params.get('hold_time') is None:
            return
        etree.SubElement(bgp_config, "hold-time").text = str(bgp_params.get('hold_time'))

    def set_bgp_config(self, params):
        self.bgp_params = params
        if (self.vnc_managed is None or self.vnc_managed == False):
            if self.bgp_config_sent:
                # user must have unset the vnc managed property, so temporaly set it
                # for deleting the existing config
                self.vnc_managed = True
                self.delete_bgp_config()
                self.vnc_managed = False
                return
            return
    # end set_bgp_config

    def _get_bgp_config_xml(self, external=False):
        if self.bgp_params is None:
            return None
        bgp_config = etree.Element("group", operation="replace")
        if external:
            etree.SubElement(bgp_config, "name").text = "__contrail_external__"
            etree.SubElement(bgp_config, "type").text = "external"
        else:
            etree.SubElement(bgp_config, "name").text = "__contrail__"
            etree.SubElement(bgp_config, "type").text = "internal"
        etree.SubElement(bgp_config, "multihop")
        local_address = etree.SubElement(bgp_config, "local-address")
        local_address.text = self.bgp_params['address']
        self._add_family_etree(bgp_config, self.bgp_params)
        self.add_bgp_auth_config(bgp_config, self.bgp_params)
        self.add_bgp_hold_time_config(bgp_config, self.bgp_params)
        etree.SubElement(bgp_config, "keep").text = "all"
        return bgp_config
    # end _get_bgp_config_xml

    def reset_bgp_config(self):
        self.routing_instances = {}
        self.bgp_params = None
        self.ri_config = None
        self.tunnel_config = None
        self.interfaces_config = None
        self.services_config = None
        self.policy_config = None
        self.firewall_config = None
        self.inet_forwarding_filter = None
        self.forwarding_options_config = None
        self.global_routing_options_config = None
        self.proto_config = None
        self.route_targets = set()
        self.bgp_peers = {}
        self.external_peers = {}
    # ene reset_bgp_config

    def delete_bgp_config(self):
        if not self.bgp_config_sent:
            return
        self.reset_bgp_config()
        self.send_netconf([], default_operation="none", operation="delete")
        self.bgp_config_sent = False
    # end delete_config

    def add_bgp_peer(self, router, params, external):
        if external:
            self.external_peers[router] = params
        else:
            self.bgp_peers[router] = params
        self.send_bgp_config()
    # end add_peer

    def delete_bgp_peer(self, router):
        if router in self.bgp_peers:
            del self.bgp_peers[router]
        elif router in self.external_peers:
            del self.external_peers[rotuer]
        else:
            return
        self.send_bgp_config()
    # end delete_bgp_peer

    def _get_neighbor_config_xml(self, bgp_config, peers):
        for peer, params in peers.items():
            nbr = etree.SubElement(bgp_config, "neighbor")
            etree.SubElement(nbr, "name").text = peer
            bgp_sessions = params.get('session')
            if bgp_sessions:
                # for now assume only one session
                session_attrs = bgp_sessions[0].get('attributes', [])
                for attr in session_attrs:
                    # For not, only consider the attribute if bgp-router is
                    # not specified
                    if attr.get('bgp_router') is None:
                        self._add_family_etree(nbr, attr)
                        self.add_bgp_auth_config(nbr, attr)
                        break
            if params.get('autonomous_system') is not None:
                etree.SubElement(nbr, "peer-as").text = str(params.get('autonomous_system'))
    # end _get_neighbor_config_xml

    def send_bgp_config(self):
        bgp_config = self._get_bgp_config_xml()
        if bgp_config is None:
            return
        proto_config = etree.Element("protocols")
        bgp = etree.SubElement(proto_config, "bgp")
        bgp.append(bgp_config)
        self._get_neighbor_config_xml(bgp_config, self.bgp_peers)
        if self.external_peers is not None:
            ext_grp_config = self._get_bgp_config_xml(True)
            bgp.append(ext_grp_config)
            self._get_neighbor_config_xml(ext_grp_config, self.external_peers)

        routing_options_config = etree.Element("routing-options")
        etree.SubElement(
            routing_options_config,
            "route-distinguisher-id").text = self.bgp_params['identifier']
        etree.SubElement(routing_options_config, "autonomous-system").text = \
            str(self.bgp_params.get('autonomous_system'))
        config_list = [proto_config, routing_options_config]
        if self.ri_config is not None:
            config_list.append(self.ri_config)
        for route_target in self.route_targets:
            comm = etree.SubElement(self.policy_config, "community")
            etree.SubElement(comm, 'name').text = route_target.replace(':', '_')
            etree.SubElement(comm, 'members').text = route_target
        if self.tunnel_config is not None:
            config_list.append(self.tunnel_config)
        if self.interfaces_config is not None:
            config_list.append(self.interfaces_config)
        if self.services_config is not None:
            config_list.append(self.services_config)
        if self.policy_config is not None:
            config_list.append(self.policy_config)
        if self.firewall_config is not None:
            config_list.append(self.firewall_config)
        if self.forwarding_options_config is not None:
            config_list.append(self.forwarding_options_config)
        if self.global_routing_options_config is not None:
            config_list.append(self.global_routing_options_config)
        if self.proto_config is not None:
            config_list.append(self.proto_config)
        self.send_netconf(config_list)
        self.bgp_config_sent = True
    # end send_bgp_config

# end PhycalRouterConfig