本文详细解释了WebLogic Server迁移过程，并且通过提供详细的指导，配以过程中每个关键步骤的截图，为执行手工迁移过程的WebLogic Server管理员提供了指导。本文还提供了在WebLogic Server NodeManager的帮助下使用JMX以编程方式执行迁移过程的指导和例子。

下载作者提供的与本文相关的文件。

术语

定义

可迁移服务

可以从一个WebLogic Server实例迁移到另一个实例并且不会丢失服务相关数据的任何服务。

目标

可以做为主机并充当不同J2EE子系统服务容器的WebLogic Server的被管理实体。

集群目标

一个或多个服务器集群在一起，作为一个通过复制和共享公共资源（例如JNDI等）来提供集群服务的实体。

服务器目标

单个WebLogic Server实例。

可迁移目标

包含一个或多个候选服务器，但任何时侯都只有一个活动服务器的虚拟目标。

候选服务器*

在迁移过程中可以作为用户首选服务器的备用服务器列表。

用户首选服务器

宿主已部署J2EE服务的当前活动服务器。

源服务器

服务迁移“出”的服务器实例。

目标服务器

服务迁移“到”的服务器实例。

JMS

Java消息服务

JTA

Java事务服务

JDBC

Java数据库连接

JMX

Java管理扩展

SAN

存储区域网络

TLOG

事务日志

参数

定义

URL

详见下述内容：

域的管理服务器的监听地址。在许多情况下，我们推荐您使用URL，因为它在管理服务器的安全环境中运行命令。

WebLogic Server的监听地址是命令的目标。如果您不能访问管理服务器而您想要设定受控服务器时，可以使用此URL。格式是主机名：端口。默认是localhost:7001。

注意：如果您想要指定一个管理端口，确定您的系统管理员已经创建了一个域中所有服务器实例的管理端口，请参见创建与配置WebLogic Server域指南中的“配置一个整个域的管理端口”

Username

用户名赋予用户完成服务器上特定URL参数请求的许可。更多有关系统管理任务许可的信息，请参见保护系统管理操作。

Password

密码与用户名相关联。如果您不设定密码参数，weblogic.Admin会要求您设定密码。如果WL_HOME\server\bin在PATH环境变量中指定，weblogic.Admin使用一套WebLogic Server库来防止密码回响。更多有关设置环境变量的信息，请参见设置Classpath。

COMMAND

WebLogic管理命令的名称，配有适当的参数。一个这样的命令“MIGRATE”,可以使用户执行迁移任务，如下所示。

arguments

控制执行中的COMMAND行为的参数。

参数

定义

-jta

指定迁移为JTA服务的迁移。

-migratabletarget

定义标志为服务迁出的服务器的配置文件。对于每个服务器，WebLogic Server都可以自动创建一个可迁移目标，命名为： “（服务器名称）_migratable” 面向JTA的JMS服务器名称。

这个可迁移目标是一个配置实体，指定了JMS服务与JTA Transaction Recovery Service的偏好服务器。

-destination

服务将要转移至的服务器名称。

-sourcedown

指定源服务器出现故障。

警告：此命令应该谨慎使用。如果源服务器事实上没有故障，而只是由于网络原因连接不上，那么服务将会在目标服务器上被激活而不从源服务器移除，导致相同服务的两个同时运行版本。这将导致事务日志或者JMS消息的崩溃。

-destinationdown

指定目标服务器出现故障。迁移至非运行服务器的JMS服务将被丢失。当将JTA Transaction Recovery Service迁移至非运行服务器时，目标服务器启动时将恢复服务。

java weblogic.Admin \

-url AdminHost:7001 \

-username adminuser \

-password adminpassword \

MIGRATE \

-migratabletarget myserver2(migratable) \

-destination myserver3

java weblogic.Admin \

-url AdminHost:7001 \

-username adminuser \

-password adminpassword \

MIGRATE -jta \

-migratabletarget myserver2(migratable) \

-destination myserver3 \

-sourcedown

C:\wls700sp5\user_projects\mydomain>setenv.cmd

C:\wls700sp5\user_projects\mydomain>java weblogic.Admin -url t3://localhost:9001 -username wls_admin

-password wls_admin MIGRATE -migratabletarget "ManagedServer1 (migratable)" -destination ManagedServer1

-destinationdown

Started attempt to migrate service(s) for ManagedServer1 (migratable) to destination server ManagedServer1 …"

Migration succeeded.

Ok

//-----------------------------------------------------------------------------//

// Listing 1. AutomaticMigration

//-----------------------------------------------------------------------------//

public class AutomaticMigration

{

  public static void main(String[] args) {

    if (args.length < 8) {

      System.out.println(

       "Usage: AutomaticMigration <admin url><source server> " +

                                  "<username> <password> " +

                                  "<destination server> " +

                                  " <source up><dest up> " +

                                  " <migrate jta>");

      System.exit(1);

    }

    String  adminurl                        = args[0];

    String  sourceServerName       = args[1];

    String  username                        = args[2];

    String  password               = args[3];

    String  destination            = args[4];

    boolean sourceup               = new Boolean(args[5]).booleanValue();

    boolean destup                 = new Boolean(args[6]).booleanValue();

    boolean migrateJTA             = new Boolean(args[7]).booleanValue();

    HealthMonitor hm      = null;

    try {

      hm = new HealthMonitor(sourceServerName, /* server name */

                             adminurl,         /* url */

                             username,         /* username */

                             password          /* password */

                            );

    } catch(Exception e) {

      System.out.println("Error creating HealthMonitor, " + e.getMessage());

      System.exit(1);

    }

    while (hm.checkHealth()) {

      try {

        Thread.sleep(5000);

      } catch (InterruptedException ignore) {}

      Thread.yield();

    }

    // prepare for migration

    String mtName = sourceServerName + " (migratable)";

    try {

      MigrationHelper.migrate(adminurl,    /* admin url */

                              username,    /* admin username */

                              password,    /* admin password */

                              mtName,      /* migratable target */

                              destination, /* destination server */

                              sourceup,    /* source server up */

                              destup,      /* destination server up */

                              migrateJTA   /* migrate JTA */

                             );

    } catch (Exception e) {

       e.printStackTrace();

       System.out.println("Migration failed" + e);

    }

  }

}   

//-----------------------------------------------------------------------------//

// Listing 2. HealthMonitor

//-----------------------------------------------------------------------------//

import java.util.Hashtable;

import java.util.Date;

import java.net.URL;

import java.net.HttpURLConnection;

import javax.naming.Context;

import javax.naming.InitialContext;

import javax.naming.NamingException;

import javax.management.InstanceNotFoundException;

import weblogic.management.MBeanHome;

import weblogic.management.configuration.ServerMBean;

import weblogic.management.runtime.JMSRuntimeMBean;

import weblogic.management.runtime.JTARuntimeMBean;

import weblogic.health.HealthState;

public class HealthMonitor

{

  private String         serverName;

  private String         adminurl;

  private String         username;

  private String         password;

  private InitialContext adminIC;  // admin server initial context

  private MBeanHome      adminMH;  // admin server mbean home

  private InitialContext ic;       // managed server mbean home

  private MBeanHome      mh;       // managed server mbean home

  private boolean            debug  = false;

  private ServerMBean        server = null;

  private JTARuntimeMBean    jta    = null;

  private JMSRuntimeMBean    jms    = null;

  public HealthMonitor(

    String serverName,

    String adminurl,

    String username,

    String password

  ) throws Exception {

    this.serverName = serverName;

    this.adminurl   = adminurl;

    this.username   = username;

    this.password   = password;

    try {

      this.ic = getInitialContext(adminurl, username, password);

    } catch(NamingException ne) {

      System.out.println(

        "Cannot get Initial Context with " + adminurl + "\n" + ne);

      throw new Exception(ne.getMessage());

    }

    try {

      this.adminMH = (MBeanHome)ic.lookup(MBeanHome.ADMIN_JNDI_NAME);  

    } catch(NamingException ne) {

      System.out.println("Admin MBean Home could not be found\n" + ne);

      throw new Exception(ne.getMessage());

    }

    try {

      this.server = (ServerMBean) adminMH.getMBean(serverName, "Server");

    } catch(InstanceNotFoundException infe) {

      System.out.println("JMSRuntimeMBean could not be found\n" + infe);

      throw new Exception(infe.getMessage());

    }

    try {

      String managedURL = new String("t3://"+

                                     server.getListenAddress()+":"+

                                        server.getListenPort());

      this.adminIC = getInitialContext(managedURL, username, password);

    } catch(NamingException ne) {

      System.out.println(

        "Cannot get Initial Context with " + adminurl + "\n" + ne);

      throw new Exception(ne.getMessage());

    }

    try {

      mh = (MBeanHome)ic.lookup(MBeanHome.JNDI_NAME+"."+serverName);  

    } catch(NamingException ne) {

      System.out.println("Admin MBean Home could not be found\n" + ne);

      throw new Exception(ne.getMessage());

    }

    try {

      jms = (JMSRuntimeMBean) mh.getRuntimeMBean(serverName+".jms", "JMSRuntime");

    } catch(InstanceNotFoundException infe) {

      System.out.println("JMSRuntimeMBean could not be found\n" + infe);

      throw new Exception(infe.getMessage());

    }

    try {

      jta = (JTARuntimeMBean) mh.getRuntimeMBean("JTARuntime", "JTARuntime");

    } catch(InstanceNotFoundException infe) {

      System.out.println("JTARuntimeMBean could not be found\n" + infe);

      throw new Exception(infe.getMessage());

    }

  }

  public boolean checkHealth() {

    HealthState jmshs = jms.getHealthState();

    HealthState jtahs = jta.getHealthState();

    boolean isJMSOk    = (jmshs.getState() == HealthState.HEALTH_OK);

    boolean isJTAOk    = (jtahs.getState() == HealthState.HEALTH_OK);

    System.out.println("JMS Health is checked on " + serverName +

                       " @ " + new Date(System.currentTimeMillis()) +

                        ", and the health " + jmshs);

    System.out.println("JTA Health is checked on " + serverName +

                       " @ " + new Date(System.currentTimeMillis()) +

                        ", and the health " + jtahs);

    if (isJMSOk && isJTAOk) {

      return true;

    } else {

      return false;

    }

  }

    private InitialContext getInitialContext(

    String ur,

    String user,

    String pwd

  ) throws NamingException {

    Hashtable env = new Hashtable();

    env.put(Context.PROVIDER_URL, ur);

    env.put(Context.INITIAL_CONTEXT_FACTORY,

            "weblogic.jndi.WLInitialContextFactory");

    env.put(Context.SECURITY_PRINCIPAL, user);

    env.put(Context.SECURITY_CREDENTIALS, pwd);

    return new InitialContext(env);

  }

}

//-----------------------------------------------------------------------------//

// Listing 3. Migration Helper

//-----------------------------------------------------------------------------//

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.BufferedReader;

/**

 * This class forms the weblogic.Admin command line syntax for

 * MIGRATE command from the arguments and executes

 * java weblogic.Admin [-url URL] -username username -password password \

 *   MIGRATE -jta -migratabletarget (migratabletarget_name|servername) \

 *  -destination servername [-sourcedown] [-destinationdown]

 */

public class MigrationHelper {

  public static void migrate(String adminURL, String adminUsername,

                      String adminPassword, String migratableTargetName,

                      String destinationServerName, boolean sourceUp,

                      boolean destUp, boolean migrateJTA) throws Exception {

    // form the command line syntax for weblogic.Admin MIGRATE command

    StringBuffer sb = new StringBuffer();

    sb.append("java weblogic.Admin");

    sb.append(" -url " + adminURL);

    sb.append(" -username " + adminUsername);

    sb.append(" -password " + adminPassword);

    sb.append(" MIGRATE ");

    sb.append(" -migratabletarget " + migratableTargetName);

    sb.append(" -destination " + destinationServerName);

    if (!sourceUp) sb.append(" -sourcedown ");

    if (!destUp) sb.append(" -destinationdown ");

    if (migrateJTA) sb.append(" -jta ");

    Runtime runtime = Runtime.getRuntime();

    Process proc = runtime.exec(sb.toString());

   // put a BufferedReader on the weblogic.Admin output

    InputStream is = proc.getInputStream();

    InputStreamReader isr = new InputStreamReader(is);

    BufferedReader br = new BufferedReader(isr);

    // read the weblogic.Admin output

    String output;

    while ((output = br.readLine()) != null) {

      System.out.println(output);

    }

    // check for weblogic.Admin command execution failure

    try {

      if (proc.waitFor() != 0) {

        System.err.println("weblogic.Admin MIGRATE command exit value = " + proc.exitValue());

      }

    } catch (InterruptedException e) {

      System.err.println(e);

    }

  }

}

<MigratableTarget Cluster="mycluster"

 ConstrainedCandidateServers="ManagedServer2,ManagedServer1"

 Name="ManagedServer1 (migratable)"

 Notes="This is a system generated default migratable target for a

 server. Do not delete manually."

 UserPreferredServer="ManagedServer1"/>

<Server Cluster="mycluster" ExpectedToRun="false"

 ListenAddress="localhost" ListenPort="7001"

 Name="ManagedServer1" NativeIOEnabled="true"

 ServerVersion="7.0.5.0">

 <COM Name="ManagedServer1"/>

 <ExecuteQueue Name="default" ThreadCount="15"/>

 <IIOP Name="ManagedServer1"/>

 <JTAMigratableTarget Cluster="mycluster"

  ConstrainedCandidateServers="ManagedServer2,ManagedServer1"

  Name="ManagedServer1" UserPreferredServer="ManagedServer1"/>

 <TARecoveryService Name="ManagedServer1"/>

 <KernelDebug Name="ManagedServer1"/>

 <Log Name="ManagedServer1"/>

 <SSL Enabled="true" HostnameVerificationIgnored="true"

  ListenPort="7002" Name="ManagedServer1"

  ServerCertificateFileName="democert.pem"

  ServerPrivateKeyAlias="demokey"

  ServerPrivateKeyPassPhrase="{3DES}qmMR/wLVNPjGmnLz/kxKEg=="/>

 <ServerDebug Name="ManagedServer1"/>

 <ServerStart Name="ManagedServer1"/>

 <WebServer Name="ManagedServer1"/>

</Server>

<MigratableTarget Cluster="mycluster"

 Name="ManagedServer2 (migratable)"

 Notes="This is a system generated default migratable target for a

 server. Do not delete manually."

 UserPreferredServer="ManagedServer2"/>

<Server Cluster="mycluster" ListenAddress="localhost"

 ListenPort="8001" Name="ManagedServer2" NativeIOEnabled="true"

 ServerVersion="7.0.5.0">

 <COM Name="ManagedServer2"/>

 <ExecuteQueue Name="default" ThreadCount="15"/>

 <IIOP Name="ManagedServer2"/>

 <JTAMigratableTarget Cluster="mycluster" Name="ManagedServer2"

  UserPreferredServer="ManagedServer2"/>

 <JTARecoveryService Name="ManagedServer2"/>

 <KernelDebug Name="ManagedServer2"/>

 <Log Name="ManagedServer2"/>

 <SSL Enabled="true" HostnameVerificationIgnored="true"

  ListenPort="8002" Name="ManagedServer2"

  ServerCertificateFileName="democert.pem"

  ServerPrivateKeyAlias="demokey"

  ServerPrivateKeyPassPhrase="{3DES}qmMR/wLVNPjGmnLz/kxKEg=="/>

 <ServerDebug Name="ManagedServer2"/>

 <ServerStart Name="ManagedServer2"/>

 <WebServer Name="ManagedServer2"/>

</Server>