3、Standby端配置

启动监听器，建立联系。但是这个时候，我们不启动standby数据库。

[oracle@SimpleLinux ~]$ lsnrctl start

LSNRCTL for Linux: Version 11.2.0.4.0 - Production on 27-APR-2014 14:32:11

Copyright (c) 1991, 2013, Oracle.All rights reserved.

Starting /u01/app/oracle/bin/tnslsnr: please wait...

TNSLSNR for Linux: Version 11.2.0.4.0 - Production

System parameter file is /u01/app/oracle/network/admin/listener.ora

Log messages written to /u01/app/diag/tnslsnr/SimpleLinux/listener/alert/log.xml

Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=SimpleLinux)(PORT=1521)))

Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=SimpleLinux)(PORT=1521)))

STATUS of the LISTENER

------------------------

AliasLISTENER

VersionTNSLSNR for Linux: Version 11.2.0.4.0 - Production

Start Date27-APR-2014 14:32:13

Uptime0 days 0 hr. 0 min. 0 sec

Trace Leveloff

SecurityON: Local OS Authentication

SNMPOFF

Listener Parameter File/u01/app/oracle/network/admin/listener.ora

Listener Log File/u01/app/diag/tnslsnr/SimpleLinux/listener/alert/log.xml

Listening Endpoints Summary...

(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=SimpleLinux)(PORT=1521)))

(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))

Services Summary...

Service "ora11g" has 1 instance(s).

Instance "ora11g", status UNKNOWN, has 1 handler(s) for this service...

Service "ora11gsy" has 1 instance(s).

Instance "ora11gsy", status UNKNOWN, has 1 handler(s) for this service...

The command completed successfully

监听器启动之后，Primary端日志循环报错信息变化，减少到心跳heartbeat错误。

Sun Apr 27 14:33:02 2014

Error 1034 received logging on to the standby

PING[ARC1]: Heartbeat failed to connect to standby 'ora11gsy'. Error is 1034.

错误代码从原来的12541，变化为1034。

[oracle@SimpleLinux ~]$ oerr ora 1034

01034, 00000, "ORACLE not available"

// *Cause: Oracle was not started up. Possible causes include the following:

//- The SGA requires more space than was allocated for it.

//- The operating-system variable pointing to the instance is

//improperly defined.

// *Action: Refer to accompanying messages for possible causes and correct

//the problem mentioned in the other messages.

//If Oracle has been initialized, then on some operating systems,

//verify that Oracle was linked correctly. See the platform

//specific Oracle documentation.

对于传递日志的ARCH进程而言，在传递日志的过程中，其实就是一个一般的client process。在访问过程中，遇到的问题和一般连接问题没有太多的差异。

Standby端启动过程。

[oracle@SimpleLinux ~]$ export ORACLE_SID=ora11gsy

[oracle@SimpleLinux ~]$ sqlplus /nolog

SQL*Plus: Release 11.2.0.4.0 Production on Sun Apr 27 14:39:18 2014

Copyright (c) 1982, 2013, Oracle.All rights reserved.

SQL> conn / as sysdba

Connected to an idle instance.

SQL> startup nomount

ORACLE instance started.

Total System Global Area372449280 bytes

Fixed Size1364732 bytes

Variable Size331353348 bytes

Database Buffers33554432 bytes

Redo Buffers6176768 bytes

Standby端alert log信息。

Sun Apr 27 14:39:32 2014

MMNL started with pid=16, OS id=2339

starting up 1 shared server(s) ...

ORACLE_BASE from environment = /u01/app

Sun Apr 27 14:40:09 2014

Using STANDBY_ARCHIVE_DEST parameter default value as USE_DB_RECOVERY_FILE_DEST

destination database instance is 'started' not 'mounted'

这个时候，Primary日志也发生变化，heartbeat错误依然，错误编号变化。

Sun Apr 27 14:39:07 2014

Error 1034 received logging on to the standby

PING[ARC1]: Heartbeat failed to connect to standby 'ora11gsy'. Error is 1034.

Sun Apr 27 14:40:10 2014

PING[ARC1]: Heartbeat failed to connect to standby 'ora11gsy'. Error is 16058.

Sun Apr 27 14:41:10 2014

PING[ARC1]: Heartbeat failed to connect to standby 'ora11gsy'. Error is 16058.

错误含义：

[oracle@SimpleLinux ~]$ oerr ora 16058

16058, 00000, "standby database instance is not mounted"

// *Cause:The Remote File Server (RFS) process on the standby database

//received an internal error.

// *Action: Check the standby alert log and RFS trace files for more

//information.

RFS进程是Oracle DG传递日志的一个重要进程。错误里面，也指出standby要启动到mount才可以。

这个时候，standby端也“感觉”到传递的问题，也在不断报错。

Sun Apr 27 14:41:10 2014

destination database instance is 'started' not 'mounted'

Sun Apr 27 14:42:10 2014

destination database instance is 'started' not 'mounted'

启动数据库到mount状态。

SQL> alter database mount;

Database altered.

Standby端日志变化：

Sun Apr 27 14:45:04 2014

alter database mount

ARCH: STARTING ARCH PROCESSES

Sun Apr 27 14:45:09 2014

ARC0 started with pid=20, OS id=2525

ARC0: Archival started

ARCH: STARTING ARCH PROCESSES COMPLETE

ARC0: STARTING ARCH PROCESSES

Sun Apr 27 14:45:10 2014

Successful mount of redo thread 1, with mount id 4242154160

Physical Standby Database mounted.

Lost write protection disabled

Sun Apr 27 14:45:11 2014

ARC1 started with pid=21, OS id=2527

Completed: alter database mount--mount结束，下面就进行接收动作。

Sun Apr 27 14:45:11 2014

ARC2 started with pid=22, OS id=2529

Sun Apr 27 14:45:11 2014

ARC3 started with pid=23, OS id=2531

ARC1: Archival started

ARC2: Archival started

ARC3: Archival started

ARC1: Becoming the 'no FAL' ARCH

Sun Apr 27 14:45:12 2014

ARC4 started with pid=24, OS id=2535

ARC2: Becoming the heartbeat ARCH

ARC2: Becoming the active heartbeat ARCH

ARC4: Archival started

ARC0: STARTING ARCH PROCESSES COMPLETE

--RFS工作

Sun Apr 27 14:45:14 2014

RFS[1]: Assigned to RFS process 2539

RFS[1]: Selected log 5 for thread 1 sequence 32 dbid -55025450 branch 843741722

Sun Apr 27 14:45:14 2014

RFS[2]: Assigned to RFS process2541

RFS[2]: Opened log for thread 1 sequence 33 dbid -55025450 branch 843741722

Archived Log entry 30 added for thread 1 sequence 33 rlc 843741722 ID 0xfcd0f891 dest 2:

Sun Apr 27 14:45:17 2014

Primary database is in MAXIMUM PERFORMANCE mode

Archived Log entry 31 added for thread 1 sequence 32 ID 0xfcd0f891 dest 1:

RFS[3]: Assigned to RFS process 2547

RFS[3]: Selected log 4 for thread 1 sequence 35 dbid -55025450 branch 843741722

Sun Apr 27 14:45:24 2014

RFS[4]: Assigned to RFS process 2553

RFS[4]: Selected log 5 for thread 1 sequence 34 dbid -55025450 branch 843741722

Sun Apr 27 14:45:35 2014

Archived Log entry 32 added for thread 1 sequence 34 ID 0xfcd0f891 dest 1:

RFS是一个服务，从日志看，是Primary端的进程来负责完成的。对应进程也的确印证。

oracle253910 14:45 ?00:00:00 oracleora11gsy (LOCAL=NO)

oracle254710 14:45 ?00:00:00 oracleora11gsy (LOCAL=NO)

oracle255310 14:45 ?00:00:00 oracleora11gsy (LOCAL=NO)

oracle257810 14:50 ?00:00:00 oracleora11gsy (LOCAL=NO)

Primary端情况如下：

Sun Apr 27 14:45:15 2014

Thread 1 advanced to log sequence 35 (LGWR switch)

Current log# 1 seq# 35 mem# 0: /u01/app/oradata/ORA11G/onlinelog/o1_mf_1_9mnjwtj9_.log

Current log# 1 seq# 35 mem# 1: /u01/app/fast_recovery_area/ORA11G/onlinelog/o1_mf_1_9mnjwvdm_.log

Sun Apr 27 14:45:15 2014

******************************************************************

LGWR: Setting 'active' archival for destination LOG_ARCHIVE_DEST_2

******************************************************************

Sun Apr 27 14:45:15 2014

ARC0: Standby redo logfile selected for thread 1 sequence 32 for destination LOG_ARCHIVE_DEST_2

LNS: Standby redo logfile selected for thread 1 sequence 35 for destination LOG_ARCHIVE_DEST_2

Sun Apr 27 14:45:23 2014

Archived Log entry 54 added for thread 1 sequence 34 ID 0xfcd0f891 dest 1:

Sun Apr 27 14:45:23 2014

Using STANDBY_ARCHIVE_DEST parameter default value as USE_DB_RECOVERY_FILE_DEST

ALTER SYSTEM SET log_archive_dest_state_2='ENABLE' SCOPE=MEMORY SID='*';

Sun Apr 27 14:45:24 2014

ARC3: Standby redo logfile selected for thread 1 sequence 34 for destination LOG_ARCHIVE_DEST_2

在ping通standby端之后，Oracle Primary就会将之前invalid状态的日志归档数据通道打通启动(自动)。日志传输开始。

4、日志Apply过程

在standby端启动应用动作。

SQL> alter database recover managed standby database using current logfile disconnect from session;

Database altered.

日志对应：

Sun Apr 27 14:55:32 2014

alter database recover managed standby database using current logfile disconnect from session

Attempt to start background Managed Standby Recovery process (ora11gsy)

Sun Apr 27 14:55:33 2014

MRP0 started with pid=29, OS id=2620

MRP0: Background Managed Standby Recovery process started (ora11gsy)

Serial Media Recovery started

Managed Standby Recovery starting Real Time Apply

Waiting for all non-current ORLs to be archived...

All non-current ORLs have been archived.

Media Recovery Log /u01/app/fast_recovery_area/ORA11GSY/archivelog/2014_04_27/o1_mf_1_32_9os9vxko_.arc

Completed: alter database recover managed standby database using current logfile disconnect from session

Media Recovery Log /u01/app/fast_recovery_area/ORA11GSY/archivelog/2014_04_27/o1_mf_1_33_9os9vtp5_.arc

Media Recovery Log /u01/app/fast_recovery_area/ORA11GSY/archivelog/2014_04_27/o1_mf_1_34_9os9w9xf_.arc

Sun Apr 27 14:56:12 2014

Media Recovery Waiting for thread 1 sequence 35 (in transit)

Recovery of Online Redo Log: Thread 1 Group 4 Seq 35 Reading mem 0

Mem# 0: /u01/app/oradata/ORA11GSY/onlinelog/o1_mf_4_9nn8pckn_.log

Mem# 1: /u01/app/fast_recovery_area/ORA11GSY/onlinelog/o1_mf_4_9nn8pjjx_.log

如此，启动完成。

5、结论

从上面的实验，我们可以了解Oracle DG的一些特性。

üDG的重要组件是监听器。一般常见的配置策略，是关闭动态注册方法，对Primary和Standby采用静态注册手段。Oracle Primary在从mount到open过程中，就会异步的进行日志传递，检查连接到standby的网络通路。而且，这个检测过程是贯彻始终的。如果数据库处在最大保护状态，相信这个检测不通过的话，Primary一定会受到影响；

ü除了监听器检查，还会有heartbeat检查过程。相信在全过程，Primary都在进行heartbeat检查，判断Redo Log是否可以正常传递。我们配置service只是指定了服务名，至于standby log位置信息，还要保证standby处在mount状态下，因为只有这个状态，实例才知道standby log的位置在哪里；

üStandby启动之后，RFS服务是通过一系列的server process来实现的。来接收日志进行存储；