关于DNS的问题，请指教

Question

我在一台主机上执行ping www.baidu.com   系统能够正常解析，但是在java程序中则提示无法解析主机名，请高手指教，谢谢！
$ ping www.baidu.com
PING www.a.shifen.com: (119.75.217.56): 56 data bytes
64 bytes from 119.75.217.56: icmp_seq=0 ttl=49 time=23 ms
64 bytes from 119.75.217.56: icmp_seq=1 ttl=49 time=22 ms
64 bytes from 119.75.217.56: icmp_seq=2 ttl=49 time=22 ms

java.net.UnknownHostException: www.baidu.com
        at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:234)
        at java.net.Socket.connect(Socket.java:556)
        at java.net.Socket.connect(Socket.java:504)
        at sun.net.NetworkClient.doConnect(NetworkClient.java:180)
        at sun.net.www.http.HttpClient.openServer(HttpClient.java:403)
        at sun.net.www.http.HttpClient.openServer(HttpClient.java:521)
        at sun.net.www.http.HttpClient.<init>(HttpClient.java:246)
        at sun.net.www.http.HttpClient.New(HttpClient.java:320)
        at sun.net.www.http.HttpClient.New(HttpClient.java:337)
        at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:83
        at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:790)
        at sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:715)
        at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:959)
        at java.net.URL.openStream(URL.java:1044)
        at com.esb.console.ipesbpermission.action.IpEsbPermissionAction.test(IpEsbPermissionAction.java:2
        at com.esb.console.ipesbpermission.action.IpEsbPermissionAction.ipQuery(IpEsbPermissionAction.java:52)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:79)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:61
        at com.opensymphony.xwork.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:35
        at com.opensymphony.xwork.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:21
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:192)
        at com.opensymphony.xwork.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:175)
        at com.opensymphony.xwork.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:86)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:115)
        at com.opensymphony.xwork.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:86)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.webwork.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:174)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:151)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.eway.framework.basecomponent.webwork.interceptor.InvalidSessionIntercepter.intercept(Unknown Source)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.eway.framework.basecomponent.webwork.interceptor.ExceptionInterceptor.intercept(Unknown Source)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.DefaultActionProxy.execute(DefaultActionProxy.java:116)
        at com.opensymphony.webwork.dispatcher.DispatcherUtils.serviceAction(DispatcherUtils.java:273)
        at com.opensymphony.webwork.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:202)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at com.eway.framework.extcomponent.ui.formconfig.filter.PagePermissionFilter.doFilter(PagePermissionFilter.java:71)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at com.eway.framework.extcomponent.roleresolver.filter.RoleResolverFilter.doFilter(RoleResolverFilter.java:52)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at com.opensymphony.webwork.dispatcher.ActionContextCleanUp.doFilter(ActionContextCleanUp.java:8
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at com.eway.framework.basecomponent.web.filter.EncodingFilter.doFilter(Unknown Source)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:19
        at com.esb.console.base.filter.DhccOpenSessionInViewFilter.doFilterInternal(DhccOpenSessionInViewFilter.java:29)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:75)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:265)
        at org.acegisecurity.intercept.web.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:107)
        at org.acegisecurity.intercept.web.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:72)
        at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
        at org.acegisecurity.ui.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:124)
        at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
        at org.acegisecurity.wrapper.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:81)
        at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
        at org.acegisecurity.ui.basicauth.BasicProcessingFilter.doFilter(BasicProcessingFilter.java:174)
        at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
        at org.acegisecurity.ui.AbstractProcessingFilter.doFilter(AbstractProcessingFilter.java:271)
        at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
        at org.acegisecurity.ui.logout.LogoutFilter.doFilter(LogoutFilter.java:110)
        at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
        at org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:249)
        at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
        at org.acegisecurity.util.FilterChainProxy.doFilter(FilterChainProxy.java:149)
        at org.acegisecurity.util.FilterToBeanProxy.doFilter(FilterToBeanProxy.java:9
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:17
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:14
        at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
        at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664)
        at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
        at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
        at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
        at java.lang.Thread.run(Thread.java:811)

Answer 1

你这个是要做DNS服务器还是什么？查看一下服务器的DNS设的什么？

Answer 2

这个问题是怎么解决的呢？

Answer 3

谢谢您的回答！！

执行nslookup www.baidu.com结果如下：

$ nslookup www.baidu.com
Server:

----------------
这该怎么办

Answer 4

$ nslookup www.baidu.com
*******

Non-authoritative answer:
www.baidu.com   canonical name = www.a.shifen.com.
Name:   www.a.shifen.com
Address: 220.181.6.18
Name:   www.a.shifen.com
Address: 220.181.6.19