创建并启动多个instance
在启动多个instance前,需要为每个instance增加一个undo tablespace, 并增加一组 redo logfile.
SQLCREATE UNDO TABLESPACE UNDOTBS2 DATAFILE '/u02/oradata/rac/rac/undotbs02.dbf' SIZE 50M REUSE AUTOEXTEND ON NEXT 5120K MAXSIZE 1000M;
SQLCREATE UNDO TABLESPACE UNDOTBS3 DATAFILE '/u02/oradata/rac/rac/undotbs03.dbf' SIZE 50M REUSE AUTOEXTEND ON NEXT 5120K MAXSIZE 1000M;
SQL ALTER DATABASE ADD LOGFILE THREAD 2 '/u02/oradata/rac/rac/redo2_1.log' SIZE 10M;
SQL ALTER DATABASE ADD LOGFILE THREAD 2 '/u02/oradata/rac/rac/redo2_2.log' SIZE 10M;
SQL ALTER DATABASE ADD LOGFILE THREAD 3 '/u02/oradata/rac/rac/redo3_1.log' SIZE 10M;
SQL ALTER DATABASE ADD LOGFILE THREAD 3 '/u02/oradata/rac/rac/redo3_1.log' SIZE 10M;
SQL
然后就可以启动多个instance了.
$ eXPort Oracle_SID=rac2
$ sqlplus /nolog
SQL*Plus: Release 9.2.0.4.0 - ProdUCtion on Fri Nov 21 15:11:16 2003
Copyright (c) 1982, 2002, Oracle Corporation. All rights reserved.
SQL conn / as sysdba;
Connected to an idle instance.
SQL startup pfile=/u01/app/oracle/product/9.2.0.4.0/dbs/initrac.ora
ORACLE instance started.
Total System Global Area 38867968 bytes
Fixed Size 451584 bytes
Variable Size 33554432 bytes
Database Buffers 4194304 bytes
Redo Buffers 667648 bytes
Database mounted.
Database opened.
SQL
然后再启动rac3.
注重:
假如SGA配置太大,启动多个instance可能会死机.
在出现Database mounted.后,到Database opened.可能会要一段时间,请耐心等待.
可以用以下语句查询,确认多个instance已经启动.
SQL select inst_id, instance_number inst_no, instance_name inst_name,
2 parallel, status, database_status db_stat, active_state stat, host_name
3 from gv$instance;
