Segment Routing with flexible N*M leaf-spine topology

segmentrouting.py

import argparse
import logging
import json
import subprocess
from requests import post, delete

from mininet.topo import Topo
from mininet.net import Mininet
from mininet.cli import CLI
from mininet.node import RemoteController, Host, OVSSwitch
from mininet.link import TCLink
#|-------------------
#|  BASIC CONFIG    |
#|-------------------

## parser
parser = argparse.ArgumentParser(
        usage="Segment Routing Test[OVS part]",
        description="Topology       : N*N leaf-spine [created by Mininet]\nSegment routing: onos-netcfg",
        formatter_class = argparse.RawTextHelpFormatter)
parser.add_argument("spine", help = "# of spine switch")
parser.add_argument("leaf", help = "# of leaf switch")
parser.add_argument("--host", help = "# of host", default=2)
parser.add_argument("--controller", help = "ip of controller", default='127.0.0.1')
args = parser.parse_args()

## logger
logging.basicConfig(level=logging.INFO)
logging.info(args)
#|---------------------------
#|    MININET HOST CLASS    |
#|---------------------------

class IpHost(Host):
    def __init__(self, name, gateway, *args, **kwargs):
        super(IpHost, self).__init__(name,*args,**kwargs)
        self.gateway = gateway

    def config(self, **kwargs):
        Host.config(self,**kwargs)
        mtu = "ifconfig " + self.name + "-eth0 mtu 1490"
        self.cmd(mtu)
        self.cmd('ip route add default via %s' % self.gateway)
#|---------------------------
#|      NETWORK CONFIG      |
#|---------------------------

netcfg = {
    "ports":{},
    "devices":{}, 
    "hosts":{}
}
#|---------------------------
#|     MININET TOPOLOGY     |
#|---------------------------

class LeafSpine(Topo):
    spineswitch = []
    leafswitch = []
    host = []
    def __init__(self, spine, leaf, host):
        Topo.__init__(self)
        # add spine switch
        for sid in range(1, spine+1):
            name = 'Spine{}'.format(sid)
            # using leftmost bit to clarify switch type
            dpid = '0{:015x}'.format(sid)
            partialMac = '{:010x}'.format(sid)
            self.spineswitch.append(self.addSwitch(name, dpid=dpid))
            netcfg["devices"]['of:{}'.format(dpid)] = {
                "segmentrouting" : {
                    "name" : name,
                    "ipv4NodeSid" : '1{:03}'.format(sid),
                    "ipv4Loopback" : '10.6.{}.254'.format(leaf + sid),
                    "routerMac" : '{}:00'.format(':'.join(partialMac[i:i+2] for i in range(0,10,2))),
                    "isEdgeRouter" : False,
                    "adjacencySids" : []
                },
                "basic" : {
                    "name" : name,
                    "driver" : "ofdpa-ovs"
                }
            }
        # add leaf switch
        for lid in range(1, leaf+1):
            name = 'Leaf{}'.format(lid)
            dpid = '1{:015x}'.format(lid)
            self.leafswitch.append(self.addSwitch(name, dpid=dpid))
            lip = '10.6.{}.254'.format(lid) 
            partialMac = '{:010x}'.format(lid)
            # lip is the gateway of those host below
            netcfg["devices"]['of:{}'.format(dpid)] = {
                "segmentrouting" : {
                    "name" : name,
                    "ipv4NodeSid" : '2{:03}'.format(lid),
                    "ipv4Loopback" : lip,
                    "routerMac" : '{}:01'.format(':'.join(partialMac[i:i+2] for i in range(0,10,2))),
                    "isEdgeRouter" : True,
                    "adjacencySids" : []
                },
                "basic" : {
                    "name" : name,
                    "driver" : "ofdpa-ovs"
                }
            }
            # add host
            for localhid in range(1, host+1):
                hid = host * (lid - 1) + localhid 
                name = 'h{}'.format(hid)
                mac = ':'.join('{:012x}'.format(hid)[i:i+2] for i in range(0,12,2))
                hip = '10.6.{}.{}/24'.format(lid, localhid)
                self.host.append(self.addHost(name, cls=IpHost, mac=mac , ip= hip, gateway=lip))
                port = spine + localhid
                netcfg["ports"]['of:{}/{}'.format(dpid,port)] = {
                    "interfaces": [
                        {
                            "ips": ['10.6.{}.254/24'.format(lid)],
                            "vlan-untagged": 20
                        }
                    ]
                }
                netcfg["hosts"]['{}/-1'.format(mac)] = {
                    "basic": {
                        "ips": ['10.6.{}.{}'.format(lid, localhid)],
                        "locations": ['of:{}/{}'.format(dpid,port)]
                    }
                }
        for i in range(leaf):
            for j in range(spine):
                self.addLink(self.leafswitch[i],self.spineswitch[j])
            for j in range(host):
                self.addLink(self.leafswitch[i], self.host[i*host + j])

# topos = {'leaf-spine': (lambda: LeafSpine())}
#|---------------------------
#|      MININET BUILD       |
#|---------------------------

if __name__ == "__main__":
    #ONOS_config
    subprocess.call("curl -X POST -u onos:rocks 'http://localhost:8181/onos/v1/applications/org.onosproject.openflow/active'",shell=True)
    subprocess.call("curl -X POST -u onos:rocks 'http://localhost:8181/onos/v1/applications/org.onosproject.segmentrouting/active'",shell=True)
    subprocess.call("curl -X POST -u onos:rocks 'http://localhost:8181/onos/v1/applications/org.onosproject.netcfghostprovider/active'",shell=True)
    subprocess.call("curl -X DELETE -u onos:rocks 'http://localhost:8181/onos/v1/applications/org.onosproject.fwd/active'",shell=True)
    
    topo = LeafSpine(int(args.spine), int(args.leaf), int(args.host))
    file = open("netcfg.json", 'w')
    file.write(json.dumps(netcfg))
    file.close()
    subprocess.call('~/onos/tools/package/runtime/bin/onos-netcfg {} netcfg.json'.format(args.controller),shell=True, executable="/bin/bash")
    net = Mininet(topo=topo, link=TCLink, controller=None)
    net.addController('c0', switch=OVSSwitch, controller=RemoteController, ip=args.controller, port=6653 )

    net.start()
    CLI(net)
    net.stop()