下面是更改的部分步骤，但是启动问题还是存在，求达人完整。 单实例的 数据库修改SID比较简单，只需要修改pfile相关参数，就可以挂载 数据库。 RAC 环境其实一样，只不过除了修改pfile，还需要修改 OCR信息。 首先来看看RAC的状态： [root@rac1 tmp]# /u01/app/crs/bin/crs_stat -t Name Type Target State Host ------------------------------------------------------------ ora.orcl.db application ONLINE ONLINE rac1 ora....l1.inst application ONLINE ONLINE rac1 ora....l2.inst application ONLINE ONLINE rac2 ora....SM1.asm application ONLINE ONLINE rac1 ora....C1.lsnr application ONLINE ONLINE rac1 ora.rac1.gsd application ONLINE ONLINE rac1 ora.rac1.ons application ONLINE ONLINE rac1 ora.rac1.vip application ONLINE ONLINE rac1 ora....SM2.asm application ONLINE ONLINE rac2 ora....C2.lsnr application ONLINE ONLINE rac2 ora.rac2.gsd application ONLINE ONLINE rac2 ora.rac2.ons application ONLINE ONLINE rac2 ora.rac2.vip application ONLINE ONLINE rac2 现在RAC状态一切正常，所有 服务已经启动。下面来试下如何修改2台RAC机器的SID，分别修改为：orcl3, orcl4 1. 创建pfile,然后把orcl1--->orcl3 orcl2--->orcl4,并传输给另外一个节点，其他参数不任何变更 SQL> conn /as sysdba Connected. SQL> create pfile='/tmp/pfile' from spfile; File created. [oracle@rac1 companion]$ scp /tmp/pfile 192.168.18.9:/tmp pfile 100% 1290 1.3KB/s 00:00 [oracle@rac1 companion]$ cat /tmp/pfile orcl4.__db_cache_size=75497472 orcl3.__db_cache_size=58720256 orcl3.__ java_pool_size=4194304 orcl4.__java_pool_size=4194304 orcl3.__large_pool_size=4194304 orcl4.__large_pool_size=4194304 orcl4.__shared_pool_size=79691776 orcl3.__shared_pool_size=96468992 orcl3.__streams_pool_size=0 orcl4.__streams_pool_size=0 *.audit_file_dest='/u01/app/oracle/admin/orcl/adump' *.background_dump_dest='/u01/app/oracle/admin/orcl/bdump' *.cluster_database_instances=2 *.cluster_database=true *.compatible='10.2.0.1.0' *.control_files='+DATA1/orcl/controlfile/current.260.696461787' *.core_dump_dest='/u01/app/oracle/admin/orcl/cdump' *.db_block_size=8192 *.db_create_file_dest='+DATA1' *.db_domain='oracle.com' *.db_file_multiblock_read_count=16 *.db_name='orcl' *.dispatchers='(PROTOCOL=TCP) (SERVICE=orclXDB)' orcl4.instance_number=2 orcl3.instance_number=1 *.job_queue_processes=10 *.log_archive_dest_1='LOCATION=+DATA1/orcl/' *.log_archive_format='%t_%s_%r.dbf' *.open_cursors=300 *.pga_aggregate_target=16777216 *.processes=150 *.remote_listener='LISTENERS_ORCL' *.remote_login_passwordfile='exclusive' *.sga_target=167772160 orcl4.thread=2 orcl3.thread=1 *.undo_management='AUTO' orcl3.undo_tablespace='UNDOTBS1' orcl4.undo_tablespace='UNDOTBS2' *.user_dump_dest='/u01/app/oracle/admin/orcl/udump' 2. 停止2台节点的数据库(2个节点运行，当然也可以使用srvctl) SQL> conn /as sysdba Connected. SQL> shutdown immediate Database clo sed. Database dismounted. ORACLE instance shut down. SQL> 再来看看状态： [root@rac1 tmp]# /u01/app/crs/bin/crs_stat -t Name Type Target State Host ------------------------------------------------------------ ora.orcl.db application OFFLINE OFFLINE ora....l1.inst application OFFLINE OFFLINE ora....l2.inst application OFFLINE OFFLINE ora....SM1.asm application ONLINE ONLINE rac1 ora....C1.lsnr application ONLINE ONLINE rac1 ora.rac1.gsd application ONLINE ONLINE rac1 ora.rac1.ons application ONLINE ONLINE rac1 ora.rac1.vip application ONLINE ONLINE rac1 ora....SM2.asm application ONLINE ONLINE rac2 ora....C2.lsnr application ONLINE ONLINE rac2 ora.rac2.gsd application ONLINE ONLINE rac2 ora.rac2.ons application ONLINE ONLINE rac2 ora.rac2.vip application ONLINE ONLINE rac2 可以看到instance都已经停止。 3. 修改 .bash_profile的ORACLE_SID的环境变量,其他的不需要修改(2个节点) export ORACLE_SID=orcl3 export ORACLE_SID=orcl4 4. 通过pfile启动数据库（2个节点运行） SQL> conn /as sysdba Connected to an idle instance. SQL> startup pfile='/tmp/pfile'; ORACLE instance started. Total System Global Area 167772160 bytes Fixed Size 1218316 bytes Variable Size 88082676 bytes Database Buffers 75497472 bytes Redo Buffers 2973696 bytes Database mounted. Database opened. 再查看相关RAC状态： [root@rac1 tmp]# /u01/app/crs/bin/crs_stat -t Name Type Target State Host ------------------------------------------------------------ ora.orcl.db application OFFLINE OFFLINE ora....l1.inst application OFFLINE OFFLINE ora....l2.inst application OFFLINE OFFLINE ora....SM1.asm application ONLINE ONLINE rac1 ora....C1.lsnr application ONLINE ONLINE rac1 ora.rac1.gsd application ONLINE ONLINE rac1 ora.rac1.ons application ONLINE ONLINE rac1 ora.rac1.vip application ONLINE ONLINE rac1 ora....SM2.asm application ONLINE ONLINE rac2 ora....C2.lsnr application ONLINE ONLINE rac2 ora.rac2.gsd application ONLINE ONLINE rac2 ora.rac2.ons application ONLINE ONLINE rac2 ora.rac2.vip application ONLINE ONLINE rac2 可以看到，虽然启动，但是由于OCR信息并没有修改，所有CRS显示出来并不正确。接下来就是要更新OCR的信息。 在修改之前，先来做个测试： 在RAC1运行; SQL> create table test(id number); Table created. SQL> insert into test values(1); 1 row created. SQL> commit; Commit complete. 在RAC2查看是否有问题： SQL> select * from test; ID ---------- 1 再继续看： SQL> show parameter instance_name NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ instance_name string orcl3 SQL> show parameter instance_name NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ instance_name string orcl4 可以看到，数据库中instance_name已经修改了。 5. 最后就是更新OCR 首先先移除原来的SID信息： 先移除数据库注册信息 Srvctl remove databse –d orcl 再移除数据库实例注册信息 [oracle@rac1 ~]$ srvctl remove instance -d orcl -i orcl1 Remove instance orcl1 from the database orcl? (y/[n]) y [oracle@rac1 ~]$ srvctl remove instance -d orcl -i orcl2 Remove instance orcl2 from the database orcl? (y/[n]) y 查看CRS状态： [root@rac1 tmp]# /u01/app/crs/bin/crs_stat -t Name Type Target State Host ------------------------------------------------------------ ora.orcl.db application OFFLINE OFFLINE ora....SM1.asm application ONLINE ONLINE rac1 ora....C1.lsnr application ONLINE ONLINE rac1 ora.rac1.gsd application ONLINE ONLINE rac1 ora.rac1.ons application ONLINE ONLINE rac1 ora.rac1.vip application ONLINE ONLINE rac1 ora....SM2.asm application ONLINE ONLINE rac2 ora....C2.lsnr application ONLINE ONLINE rac2 ora.rac2.gsd application ONLINE ONLINE rac2 ora.rac2.ons application ONLINE ONLINE rac2 ora.rac2.vip application ONLINE ONLINE rac2 信息已经移除，接下来就是重新注册新的instance了。 [oracle@rac1 ~]$ srvctl add instance -d orcl -i orcl3 -n rac1 [oracle@rac1 ~]$ srvctl add instance -d orcl -i orcl4 -n rac2 查看CRS状态： [root@rac1 tmp]# /u01/app/crs/bin/crs_stat -t Name Type Target State Host ------------------------------------------------------------ ora.orcl.db application OFFLINE OFFLINE ora....l3.inst application OFFLINE OFFLINE ora....l4.inst application OFFLINE OFFLINE ora....SM1.asm application ONLINE ONLINE rac1 ora....C1.lsnr application ONLINE ONLINE rac1 ora.rac1.gsd application ONLINE ONLINE rac1 ora.rac1.ons application ONLINE ONLINE rac1 ora.rac1.vip application ONLINE ONLINE rac1 ora....SM2.asm application ONLINE ONLINE rac2 ora....C2.lsnr application ONLINE ONLINE rac2 ora.rac2.gsd application ONLINE ONLINE rac2 ora.rac2.ons application ONLINE ONLINE rac2 ora.rac2.vip application ONLINE ONLINE rac2 已经注册成功，可以发现instance变为orcl3,orcl4了。 后面缺少重建SPFILE 文件的步骤。。。。 感觉可以用create spfile from pfile='/tmp/pfile';,来覆盖 但是不确定