Python AutoNetkit.asn方法代码示例

# 需要导入模块: import AutoNetkit [as 别名]
# 或者: from AutoNetkit import asn [as 别名]
def allocate_dns_servers(network):
    """Allocates DNS according to rules defined above
    
    TODO: allow 3 level (ie no pop caching, clients connect to AS server)
    TODO: make DNS servers standalone rather that co-hosted with router
    
    TODO: note set dns level on dns graph, but ibgp level on physical graph - inconsistent!
    
    """
    dns_graph = nx.DiGraph()
    dns_advertise_graph = nx.DiGraph()
    LOG.debug("DNS currently disabled")

    hierarchical_dns = config.settings['DNS']['hierarchical']
    if hierarchical_dns:
        LOG.info("Configuring hierarchical DNS")
        dns_levels = 4
    else:
        dns_levels = 1
        LOG.debug("Non-hierarchical DNS not yet implemented")
#TODO: do "flat" dns - one root server, add all other devices as children for both resolving and authoritative

        return


    def nodes_by_eccentricity(graph):
        if len(graph) == 1:
            return graph.nodes()
# need to crop the global shortest paths otherwise get 
#NetworkXError: Graph not connected: infinite path length
        eccentricities = nx.eccentricity(graph)
        return sorted(eccentricities.keys(), key = lambda n: eccentricities[n])

    def format_asn(asn):
        """Returns unique format for asn, so don't confuse with property of the same,
        eg if ibgp_l2_cluster = 1 in as2, it could match as1 routers as 1==1
        so set asn_1 so 1 != asn_1"""
        return "asn_%s" % asn

    def get_l2_cluster(node):
        """syntactic sugar to access cluster"""
        return dns_graph.node[node].get("dns_l2_cluster")

    def get_l3_cluster(node):
        """syntactic sugar to access cluster"""
        return dns_graph.node[node].get("dns_l3_cluster")

    def level(u):
        return int(dns_graph.node[u]['level'])

    servers_per_l2_cluster = config.settings['DNS']['Server Count']['l2 cluster'] 
    servers_per_l3_cluster = config.settings['DNS']['Server Count']['l3 cluster'] 
    root_dns_servers = config.settings['DNS']['Server Count']['root'] 
    global_eccentricities = nodes_by_eccentricity(network.graph)


#TODO: add count of each cluster occurence so can round servers down - dont want 3 servers in a one router network!

# Add routers, these form the level 1 clients
    dns_graph.add_nodes_from(network.graph.nodes(), level=1)
    for node, data in network.graph.nodes(data=True):
        #TODO: the cluster should never be manually set, so can remove checks
        if not data.get("dns_l2_cluster"):
            dns_graph.node[node]['dns_l2_cluster'] = data.get("pop") or format_asn(network.asn(node))
        if not data.get("dns_l3_cluster"):
            dns_graph.node[node]['dns_l3_cluster'] = format_asn(network.asn(node))

    for my_as in ank.get_as_graphs(network):
        asn = my_as.asn
        if not nx.is_strongly_connected(my_as):
            LOG.info("AS%s not fully connected, skipping DNS configuration" % asn)
            continue

        l2_clusters = list(set(dns_graph.node[n].get("dns_l2_cluster") for n in my_as))
        for l2_cluster in l2_clusters:
            for index in range(servers_per_l2_cluster):
                label = "l2_%s_dns_%s" % (l2_cluster, index+1)
                if l2_cluster == format_asn(asn):
# Don't put asn into server name twice "AS2_asn_2_l2dns_1" vs "asn_2_l2dns_1"
                    server_name = "%s_l2dns_%s" % (l2_cluster, index+1)
                else:
                    server_name = "AS%s_%s_l2dns_%s" % (asn, l2_cluster, index+1)
#TODO: see what other properties to retain
                node_name = network.add_device(server_name, asn=asn, 
                        device_type='server', label=label)
                dns_graph.add_node(node_name, level=2, dns_l2_cluster=l2_cluster,
                        asn = asn, dns_l3_cluster = format_asn(asn))

        for index in range(servers_per_l3_cluster):
                label = "l3_%s_dns_%s" % (asn, index+1)
                server_name = "AS%s_l3dns_%s" % (asn, index+1)
                node_name = network.add_device(server_name, asn=asn, 
                        device_type='server', label=label)
#TODO: check if need to add l2 here - was coded before, possible mistake?
                dns_graph.add_node(node_name, level=3, 
                        asn = asn, dns_l3_cluster = format_asn(asn))
    
    # and level 4 connections
#TODO: need to determine the right place to put the server - order issue between allocating for root as need an ASN for the device before  know best place - for now use asn = 1, and move if needed
    for index in range(root_dns_servers):
#.........这里部分代码省略.........