Netty Sctp Heartbeat on wrong Interface

Question

I am using a NioSctpServerChannel connection with Netty between two different machines. The connection is established successfully and receives data after the client's channelActive-Handler sends some data to the server.

The receiving interface seems to be another than the binding interface (192.168.122.1 instead of 192.168.243.31) - is this a system or netty problem?

Then a heartbeat is sent via a complete different interface (in this case a virbr 192.168.122.1) and is answered with an abort which destroys the connection. When the client tries to send a heartbeat this is logically also answered with an abort since the connection is already down.

PC1 192.168.243.31 (Server) PC2 192.168.243.12 (Client)

Server Init Code:

public void run() throws Exception {
    EventLoopGroup bossGroup = new NioEventLoopGroup(1);
    EventLoopGroup workerGroup = new NioEventLoopGroup();
    try {
        ServerBootstrap b = new ServerBootstrap();
        b.group(bossGroup, workerGroup)
                .channel(NioSctpServerChannel.class)
                .option(ChannelOption.SO_BACKLOG, 100)
                .handler(new LoggingHandler(LogLevel.INFO))
                .option(ChannelOption.SO_KEEPALIVE, true)
                .childHandler(new ChannelInitializer<SctpChannel>() {
                    @Override
                    public void initChannel(SctpChannel ch) throws Exception {
                        ch.pipeline().addLast(new Handler1());
                        ch.pipeline().addLast(new Handler2());
                        ch.pipeline().addLast(new Handler3());
                    }
                });

        System.out.println("Connector binding...");
        ChannelFuture f = b.bind("192.168.243.31", port).sync();
        f.channel().closeFuture().sync();
    } finally {
        bossGroup.shutdownGracefully();
        workerGroup.shutdownGracefully();
    }
    System.out.println("Connector ended.");
}

LOG Output:

Running Staging Server ...
Connector binding...
Jul 03, 2014 8:05:27 AM io.netty.handler.logging.LoggingHandler channelRegistered
INFO: [id: 0xef4ebad6] REGISTERED
Jul 03, 2014 8:05:27 AM io.netty.handler.logging.LoggingHandler bind
INFO: [id: 0xef4ebad6] BIND: /192.168.243.31:8090
Jul 03, 2014 8:05:27 AM io.netty.handler.logging.LoggingHandler channelActive
INFO: [id: 0xef4ebad6, /192.168.243.31:8090] ACTIVE
Jul 03, 2014 8:05:33 AM io.netty.handler.logging.LoggingHandler channelRead
INFO: [id: 0xef4ebad6, /192.168.243.31:8090] RECEIVED: [id: 0x2a9c7ea3, /192.168.122.1:49423 => /192.168.243.31:8090]
HandlerActive
Data rx:
--------------------------------------------------------------------------------
      00 01 02 03  04 05 06 07  08 09 0a 0b  0c 0d 0e 0f 

0000  a8 2b 0a 31  03 32 03 16  0d 28 36                  .+.1.2...(6
--------------------------------------------------------------------------------
java.net.SocketException: Connection reset by peer
    at sun.nio.ch.sctp.SctpChannelImpl.receive0(Native Method)
    at sun.nio.ch.sctp.SctpChannelImpl.receiveIntoNativeBuffer(SctpChannelImpl.java:860)
    at sun.nio.ch.sctp.SctpChannelImpl.receive(SctpChannelImpl.java:836)
    at sun.nio.ch.sctp.SctpChannelImpl.receive(SctpChannelImpl.java:779)
    at sun.nio.ch.sctp.SctpChannelImpl.receive(SctpChannelImpl.java:741)
    at io.netty.channel.sctp.nio.NioSctpChannel.doReadMessages(NioSctpChannel.java:278)
    at io.netty.channel.nio.AbstractNioMessageChannel$NioMessageUnsafe.read(AbstractNioMessageChannel.java:73)
    at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:485)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:452)
    at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:346)
    at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:794)
    at java.lang.Thread.run(Thread.java:745)
channelInactive

network configuration:

br1       Link encap:Ethernet  HWaddr 00:e0:7d:ae:bc:6f  
      inet addr:10.10.0.1  Bcast:10.10.255.255  Mask:255.255.0.0
      inet6 addr: fe80::2e0:7dff:feae:bc6f/64 Scope:Link
      UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
      RX packets:11 errors:0 dropped:0 overruns:0 frame:0
      TX packets:38 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:0 
      RX bytes:506 (506.0 B)  TX bytes:7288 (7.2 KB)

br2       Link encap:Ethernet  HWaddr 64:31:50:3f:4e:01  
      inet addr:192.168.243.31  Bcast:192.168.243.255  Mask:255.255.255.0
      inet6 addr: fe80::6631:50ff:fe3f:4e01/64 Scope:Link
      UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
      RX packets:96536 errors:0 dropped:0 overruns:0 frame:0
      TX packets:54325 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:0 
      RX bytes:102780133 (102.7 MB)  TX bytes:19776526 (19.7 MB)

eth0      Link encap:Ethernet  HWaddr 00:e0:7d:ae:bc:6f  
      UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
      RX packets:274 errors:0 dropped:0 overruns:0 frame:0
      TX packets:849 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:1000 
      RX bytes:16440 (16.4 KB)  TX bytes:61267 (61.2 KB)

eth1      Link encap:Ethernet  HWaddr 64:31:50:3f:4e:01  
      UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
      RX packets:121985 errors:0 dropped:68 overruns:0 frame:0
      TX packets:60157 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:1000 
      RX bytes:106326525 (106.3 MB)  TX bytes:20402116 (20.4 MB)
      Interrupt:19 Memory:f0100000-f0120000 

lo        Link encap:Local Loopback  
      inet addr:127.0.0.1  Mask:255.0.0.0
      inet6 addr: ::1/128 Scope:Host
      UP LOOPBACK RUNNING  MTU:65536  Metric:1
      RX packets:444 errors:0 dropped:0 overruns:0 frame:0
      TX packets:444 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:0 
      RX bytes:53204 (53.2 KB)  TX bytes:53204 (53.2 KB)

virbr0    Link encap:Ethernet  HWaddr 82:34:aa:4d:49:4e  
      inet addr:192.168.122.1  Bcast:192.168.122.255  Mask:255.255.255.0
      UP BROADCAST MULTICAST  MTU:1500  Metric:1
      RX packets:0 errors:0 dropped:0 overruns:0 frame:0
      TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:0 
      RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

Network traffic:

1444    27.462912000    192.168.243.12  192.168.243.31  SCTP    116 INIT 
1445    27.463024000    192.168.243.31  192.168.243.12  SCTP    340 INIT_ACK 
1446    27.463030000    192.168.243.31  192.168.243.12  SCTP    340 INIT_ACK 
1447    27.463702000    192.168.243.12  192.168.243.31  SCTP    312 COOKIE_ECHO 
1448    27.463702000    192.168.243.12  192.168.243.31  SCTP    312 COOKIE_ECHO 
1449    27.463786000    192.168.243.31  192.168.243.12  SCTP    52  COOKIE_ACK 
1450    27.463798000    192.168.243.31  192.168.243.12  SCTP    52  COOKIE_ACK 
1451    27.469117000    192.168.243.12  192.168.243.31  SCTP    76  DATA 
1452    27.469117000    192.168.243.12  192.168.243.31  SCTP    76  DATA 
1453    27.469160000    192.168.243.31  192.168.243.12  SCTP    64  SACK 
1454    27.469164000    192.168.243.31  192.168.243.12  SCTP    64  SACK 
1520    30.097581000    192.168.243.31  192.168.122.1   SCTP    100 HEARTBEAT 
1521    30.097638000    192.168.122.1   192.168.243.31  SCTP    52  ABORT 
2184    59.710594000    192.168.243.12  192.168.243.31  SCTP    96  HEARTBEAT 
2185    59.710594000    192.168.243.12  192.168.243.31  SCTP    96  HEARTBEAT 
2186    59.710638000    192.168.243.31  192.168.243.12  SCTP    52  ABORT 
2187    59.710641000    192.168.243.31  192.168.243.12  SCTP    52  ABORT 1

I'm not sure if this is a Netty problem. Did you try to write a simplistic SCTP application using plain Netty-free Java, to see the problem is still there? — trustin, Jul 03 '14 at 09:29

score 0 · Answer 1 · answered Jul 04 '14 at 07:40

I solved the problem:

The Client has to bind to a specific IP-Address. Otherwise all interface addresses are sent within sctp. If there are the same Interface IP Addresses per coincidence :-( the Heartbeat is transmitted to your own interface...

Tom

Netty Sctp Heartbeat on wrong Interface

1 Answers1