我们的处境非常残酷。我们在德国有一个网站，它是一家在线商店。一天多次，我们有大量处于 CLOSE_WAIT 状态的连接出现在 netstat 中，来自同一个 IP。不同的IP，但都在中国。我们确实还有中国客户。检查访问日志，我们看到来自问题ip的流量来自一个浏览器（useragent，session id），但它看起来不像真正的流量，例如连续请求/ 500次，没有请求css ,js,它背后的图像。所以我们最终得到的是在 socketWrite0 中有 1000 个线程，其中 820 个线程将绑定到相同的 ip：
"http--0.0.0.0-8443-1201" daemon prio=10 tid=0x00007f7435257800 nid=0x5361 runnable [0x00007f73e162a000]
java.lang.Thread.State: RUNNABLE
at java.net.SocketOutputStream.socketWrite0(Native Method)
at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:109)
at java.net.SocketOutputStream.write(SocketOutputStream.java:153)
at org.apache.coyote.http11.InternalOutputBuffer.realWriteBytes(InternalOutputBuffer.java:724)
at org.apache.tomcat.util.buf.ByteChunk.flushBuffer(ByteChunk.java:449)
at org.apache.tomcat.util.buf.ByteChunk.append(ByteChunk.java:349)
at org.apache.coyote.http11.InternalOutputBuffer$OutputStreamOutputBuffer.doWrite(InternalOutputBuffer.java:748)
at org.apache.coyote.http11.filters.ChunkedOutputFilter.doWrite(ChunkedOutputFilter.java:126)
at org.apache.coyote.http11.InternalOutputBuffer.doWrite(InternalOutputBuffer.java:559)
at org.apache.coyote.Response.doWrite(Response.java:594)
at org.apache.catalina.connector.OutputBuffer.realWriteBytes(OutputBuffer.java:398)
at org.apache.tomcat.util.buf.ByteChunk.flushBuffer(ByteChunk.java:449)
at org.apache.catalina.connector.OutputBuffer.realWriteChars(OutputBuffer.java:473)
at org.apache.tomcat.util.buf.CharChunk.flushBuffer(CharChunk.java:469)
at org.apache.tomcat.util.buf.CharChunk.append(CharChunk.java:295)
at org.apache.catalina.connector.OutputBuffer.write(OutputBuffer.java:505)
at org.apache.catalina.connector.CoyoteWriter.write(CoyoteWriter.java:143)
at org.apache.catalina.connector.CoyoteWriter.write(CoyoteWriter.java:152)
at com.sun.faces.application.view.WriteBehindStateWriter.flushToWriter(WriteBehindStateWriter.java:240)
at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:419)
at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:125)
at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:288)
at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:288)
at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:121)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:594)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:329)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:840)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:622)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:560)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:488)
at x.y.z.common.web.dispatch.StartPageDispatcherServlet.forward(StartPageDispatcherServlet.java:52)
at x.y.z.common.web.dispatch.StartPageDispatcherServlet.service(StartPageDispatcherServlet.java:37)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:329)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248)
at org.jboss.weld.servlet.ConversationPropagationFilter.doFilter(ConversationPropagationFilter.java:62)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248)
at net.anotheria.moskito.web.MoskitoFilter.doFilter(MoskitoFilter.java:110)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248)
at net.anotheria.moskito.web.MoskitoFilter.doFilter(MoskitoFilter.java:110)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248)
at net.anotheria.moskito.web.filters.JourneyFilter.doFilter(JourneyFilter.java:84)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248)
at net.anotheria.moskito.web.filters.MoskitoCommandFilter.doFilter(MoskitoCommandFilter.java:26)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248)
at x.y.z.common.web.useragent.TouchScreenDeviceFilter.doFilter(TouchScreenDeviceFilter.java:42)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248)
at x.y.z.common.web.LandingPageFilter.doFilter(LandingPageFilter.java:44)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248)
at x.y.z.common.web.CharsetFilter.doFilter(CharsetFilter.java:53)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:275)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:397)
at org.jboss.as.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50)
at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:153)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:155)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.jboss.web.rewrite.RewriteValve.invoke(RewriteValve.java:466)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:567)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:368)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:877)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:671)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:930)
at java.lang.Thread.run(Thread.java:722)
grepping netstat 输出显示此 ip 在 CLOSE_WAIT 中有 817 个连接，在 ESTABLISHED 状态中有 3 个连接。
访问日志显示：
140.206.78.100 [13/Feb/2013:15:20:48 +0100] http--0.0.0.0-8443-364 GET o1uNdliDOQhJkDnbvXo4RIZ2.undefined 1276 HTTP/1.1 443 / 200 Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.95 Safari/537.11
140.206.78.100 [13/Feb/2013:15:20:50 +0100] http--0.0.0.0-8443-364 GET o1uNdliDOQhJkDnbvXo4RIZ2.undefined 1259 HTTP/1.1 443 / 200 Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.95 Safari/537.11
140.206.78.100 [13/Feb/2013:15:20:51 +0100] http--0.0.0.0-8443-477 GET o1uNdliDOQhJkDnbvXo4RIZ2.undefined 2991 HTTP/1.1 443 / 200 Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.95 Safari/537.11
140.206.78.100 [13/Feb/2013:15:20:53 +0100] http--0.0.0.0-8443-428 GET o1uNdliDOQhJkDnbvXo4RIZ2.undefined 2456 HTTP/1.1 443 / 200 Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.95 Safari/537.11
140.206.78.100 [13/Feb/2013:15:20:54 +0100] http--0.0.0.0-8443-639 GET o1uNdliDOQhJkDnbvXo4RIZ2.undefined 1305 HTTP/1.1 443 / 200 Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.95 Safari/537.11
140.206.78.100 [13/Feb/2013:15:20:54 +0100] http--0.0.0.0-8443-491 GET o1uNdliDOQhJkDnbvXo4RIZ2.undefined 1326 HTTP/1.1 443 / 200 Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.95 Safari/537.11
140.206.78.100 [13/Feb/2013:15:20:56 +0100] http--0.0.0.0-8443-491 GET o1uNdliDOQhJkDnbvXo4RIZ2.undefined 1293 HTTP/1.1 443 / 200 Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.95 Safari/537.11
140.206.78.100 [13/Feb/2013:15:20:57 +0100] http--0.0.0.0-8443-663 GET o1uNdliDOQhJkDnbvXo4RIZ2.undefined 1315 HTTP/1.1 443 / 200 Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.95 Safari/537.11
140.206.78.100 [13/Feb/2013:15:20:59 +0100] http--0.0.0.0-8443-663 GET o1uNdliDOQhJkDnbvXo4RIZ2.undefined 1277 HTTP/1.1 443 / 200 Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.95 Safari/537.11
140.206.78.100 [13/Feb/2013:15:21:02 +0100] http--0.0.0.0-8443-225 GET o1uNdliDOQhJkDnbvXo4RIZ2.undefined 2427 HTTP/1.1 443 / 200 Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.95 Safari/537.11
1
我们使用 Jboss AS 7、java 6/7（两者都试过）、vm 上的 ubuntu、ssl 卸载和使用 alteon 负载平衡器的负载平衡。
PS：添加了 netstat 示例，其中三个：
tcp 0 0 my.public.ip:8443 140.206.78.100:14186 ESTABLISHED
tcp 0 35040 my.public.ip:8443 140.206.78.100:14620 ESTABLISHED
tcp 0 35040 my.public.ip:8443 140.206.78.100:13859 ESTABLISHED
其中817个：
tcp 1 35040 my.public.ip:8443 140.206.78.100:13233 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:11649 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:11605 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:11892 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:13692 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:11988 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:13055 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:13242 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:13073 CLOSE_WAIT
tcp 1 37960 my.public.ip:8443 140.206.78.100:10176 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:14557 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:12288 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:12509 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:11049 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:11839 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:14208 CLOSE_WAIT
tcp 1 35040 my.public.ip:8443 140.206.78.100:14662 CLOSE_WAIT