SDN – Page 2 – Mvision

Liu Wenmao
May 7
to openstack
hi

I use quantum grizzly with namespace and floodlight, but VMs can not ping its gateway. It seems that floodlight ignore devices whose status is PORT_DOWN or LINK_DOWN, somehow the subnetwork gateway is really PORT_DOWN and LINK_DOWN.. is it normal?or how can I change its status to normal?

root@controller:~# ovs-ofctl show br-int
OFPT_FEATURES_REPLY (xid=0x1): ver:0x1, dpid:0000e2ed9e9b6942
n_tables:255, n_buffers:256
features: capabilities:0xc7, actions:0xfff
 1(qr-c5496165-c7): addr:5e:67:22:5b:d5:0e
     config:     PORT_DOWN
     state:      LINK_DOWN
 2(qr-8af2e01f-bb): addr:e4:00:00:00:00:00<--------------------this is the gateway.....
     config:     PORT_DOWN
     state:      LINK_DOWN
 3(qr-48c69382-4f): addr:22:64:6f:3a:9f:cd
     config:     PORT_DOWN
     state:      LINK_DOWN
 4(patch-tun): addr:8e:90:4c:aa:d2:06
     config:     0
     state:      0
 5(tap5b5891ac-94): addr:6e:52:f7:c1:ef:f4
     config:     PORT_DOWN
     state:      LINK_DOWN
 6(tap09a002af-66): addr:c6:cb:01:60:3f:8a
     config:     PORT_DOWN
     state:      LINK_DOWN
 7(tap160480aa-84): addr:96:43:cc:05:71:d5
     config:     PORT_DOWN
     state:      LINK_DOWN
 8(tapf6040ba0-b5): addr:e4:00:00:00:00:00
     config:     PORT_DOWN
     state:      LINK_DOWN
 9(tap0ded1c0f-df): addr:12:c8:b3:5c:fb:6a
     config:     PORT_DOWN
     state:      LINK_DOWN
 10(tapaebb6140-31): addr:e4:00:00:00:00:00
     config:     PORT_DOWN
     state:      LINK_DOWN
 11(tapddc3ce63-2b): addr:e4:00:00:00:00:00
     config:     PORT_DOWN
     state:      LINK_DOWN
 12(qr-9b9a3229-19): addr:e4:00:00:00:00:00
     config:     PORT_DOWN
     state:      LINK_DOWN
 LOCAL(br-int): addr:e2:ed:9e:9b:69:42
     config:     PORT_DOWN
     state:      LINK_DOWN
OFPT_GET_CONFIG_REPLY (xid=0x3): frags=normal miss_send_len=0

floodlight codes:
if (entity.hasSwitchPort() &&
!topology.isAttachmentPointPort(entity.getSwitchDPID(),
entity.getSwitchPort().shortValue())) {
if (logger.isDebugEnabled()) {
logger.debug("Not learning new device on internal"
+ " link: {}", entity);
}

public boolean portEnabled(OFPhysicalPort port) {
if (port == null)
return false;
if ((port.getConfig() & OFPortConfig.OFPPC_PORT_DOWN.getValue()) > 0)
return false;

这两天简单看了一下Floodlight的模块机制，大概了解了其插件的机制和流程，编写了一个非常简单的模块，为大家分享一下

Floodlight加载和运行模块的原理

Floodlight的入口是net.floodlightcontroller.core.Main，在这个类的main函数中，使用FloodlightModuleLoader加载所有的模块，然后再调用net.floodlightcontroller.restserver.RestApiServer模块的run方法，启动 rest服务器，最后调用net.floodlightcontroller.core.internal.Controller模块的 run方法，启动网络控制器。

 
   public static void main(String[] args) throws FloodlightModuleException {
        ...
        FloodlightModuleLoader fml = new FloodlightModuleLoader();
        IFloodlightModuleContext moduleContext = fml.loadModulesFromConfig(settings.getModuleFile());
        IRestApiService restApi = moduleContext.getServiceImpl(IRestApiService.class);
        restApi.run();
        IFloodlightProviderService controller =
                moduleContext.getServiceImpl(IFloodlightProviderService.class);
        controller.run();
    }

在加载模块的过程中，使用 FloodlightModuleLoader类的findAllModules方法寻找所有在$CLASSPATH路径中的实现了 net.floodlightcontroller.core.module.IFloodlightModule接口的模块，然后用initModules 初始化这些模块，最后用startupModules启动这些模块。

FloodlightModuleLoad.java:303

    initModules(moduleSet);
    startupModules(moduleSet);

以MemoryStorageSource类为例，它继承了 NoSqlStorageSource类，后者又继承了AbstractStorageSource类，而 AbstractStorageSource是实现了IFloodlightModule和 IStorageSourceService两个接口。

IFloodlightModule有一个init方法和一个startUp方法，所以MemoryStorageSource会分别实现这两个方法，并在初始化和启动的时候被调用。

一个模块的简单实例

下面简单介绍如何新建一个模块的过程，以一个IDSController为例，现在只实现定时打印日志的功能：

1 定义服务com.nsfocus.ids.IIntrusionDetectionService:

 
public interface IIntrusionDetectionService  extends IFloodlightService {
}

2 新建一个实现IFloodlightModule接口的类com.nsfocus.ids.IDSController：

分别实现接口IFloodlightModule的 getModuleServices、getServiceImpls、getModuleDependencies等方法，这三个方法主要用于初始化模块

系统运行 ServiceLoader.load(IFloodlightModule.class, cl)后会将IDSController加载到支持IFloodlightModule模块的列表中。

3 在配置文件中添加新模块：

在target\bin\floodlightdefault.properties添加：

net.floodlightcontroller.perfmon.PktInProcessingTime,\
net.floodlightcontroller.ui.web.StaticWebRoutable,\
com.nsfocus.ids.IDSController
net.floodlightcontroller.restserver.RestApiServer.port = 8080

这样新模块在加载时就被添加到集合configMods中

此外，要在bin\META-INF\services\net.floodlightcontroller.core.module.ISecurityControllerModule中添加一行

com.nsfocus.ids.IDSController

代码在运行到FloodlightModuleLoader.findAllModules的ServiceLoader.load方法时，会加载第二个文件中所列的所有模块，如果只在第一个文件中列出来，而没有在第二个文件中模块列出来的话，会抛出SecurityControllerModuleException的异常。所以一定要在两个文件中都添加该模块。

4 在IDSController中添加相应的功能

4.1 添加初始化代码

@Override
public void init(FloodlightModuleContext context) throws FloodlightModuleException {
    threadPool = context.getServiceImpl(IThreadPoolService.class);
    Map<String, String> configOptions = context.getConfigParams(this); 
    try {
        String detectTimeout = configOptions.get("detecttimeout");
        if (detectTimeout != null) {
            DETECT_TASK_INTERVAL = Short.parseShort(detectTimeout);
        }
     } catch (NumberFormatException e) {
        log.warn("Error parsing detecting timeout, " +
            "using default of {} seconds",
            DETECT_TASK_INTERVAL);
     }
     log.debug("NSFOCUS IDS controller initialized");
}

4.2 添加启动代码

@Override
public void startUp(FloodlightModuleContext context) {
    log.debug("NSFOCUS IDS controller started");
    ScheduledExecutorService ses = threadPool.getScheduledExecutor();
    detectTask = new SingletonTask(ses, new Runnable() {
        @Override
        public void run() {
            try {
                detect();
                detectTask.reschedule(DETECT_TASK_INTERVAL, TimeUnit.SECONDS);
            } catch (Exception e) {
                log.error("Exception in IDS detector", e);
            } finally {
            }
        }
     });
    detectTask.reschedule(DETECT_TASK_INTERVAL, TimeUnit.SECONDS);
}
public void detect(){
   log.debug("Detecting...");
}

这样，floodlight在初始化时自动调用IDSController的 init方法，随后在启动时会自动调用IDSController的startUp方法，上面代码使用了定时器，实现定时触发的功能。

下面是部分启动日志：

16:02:51.242 [main] DEBUG n.f.core.internal.Controller – OFListeners for PACKET_IN: linkdiscovery,topology,devicemanager,firewall,forwarding,

16:02:51.302 [main] INFO n.f.core.internal.Controller – Listening for switch connections on 0.0.0.0/0.0.0.0:6633

16:02:53.611 [debugserver-main] INFO n.f.jython.JythonServer – Starting DebugServer on port 6655

16:02:55.095 [pool-3-thread-15] DEBUG com.nsfocus.ids.IDSController – Detecting…

16:02:59.096 [pool-3-thread-11] DEBUG com.nsfocus.ids.IDSController – Detecting…

P.S. 其他成员变量声明为：

    protected static Logger log = LoggerFactory.getLogger(IDSController.class);
    protected SingletonTask detectTask;
    protected int DETECT_TASK_INTERVAL = 2;
    protected IThreadPoolService threadPool;

Category: SDN

floodlight ignore subnet gateway due to PORT_DOWN and LINK_DOWN

Floodlight加载和运行模块的原理