需求:在同一个环境下新建Standby RAC库,即和Primary RAC在相同的磁盘组。

说明:生产环境一般不建议这样配置DG,因为存储层面是相同磁盘组,灾备的实际意义不大。我这里是客户特殊场景的要求。

基本信息:

db_name: jyzhao

Primary RAC db_unique_name:jyzhao

Standby RAC db_unique_name:jyzhaodg

Standby RAC instance_name: jyzhaodg1, jyzhaodg2

版本:GI 11.2.0.4 + DB 11.2.0.4

第一章 准备工作

第二章 源数据库备份

第三章 参数文件

第四章 rman恢复控制文件

第五章 rman恢复数据库

第六章 备库开启日志应用

第七章 创建standby log

第八章 检查资源状态

第一章 准备工作

1.1 ASM存储

确认RAC Standby存储是在和RAC Primary相同的ASM磁盘组内(PS:灾备效果不明显),创建RAC Standby存储目录(根据db_unique_name)

mkdir +DATA/JYZHAODG
mkdir +FRA/JYZHAODG

1.2 配置tnsnames.ora

cd $ORACLE_HOME/network/admin/
cat tnsnames.ora
添加主库备库的连接信息(所有节点):

JYZHAO =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = oradb-scan)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = jyzhao)
)
) jyzhaodg =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = oradb-scan)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = jyzhaodg)
)
)

1.3 密码文件

节点1:

export ORACLE_SID=jyzhaodg1
密码文件;
cd $ORACLE_HOME/dbs
orapwd file=orapwjyzhaodg1 password=oracle entries=5
或者直接copy之前的密码文件,然后mv重命名:
cp orapwjyzhao1 orapwjyzhaodg1

节点2:

export ORACLE_SID=jyzhaodg2
密码文件;
cd $ORACLE_HOME/dbs
orapwd file=orapwjyzhaodg2 password=oracle entries=5
或者直接copy之前的密码文件,然后mv重命名:
cp orapwjyzhao2 orapwjyzhaodg2

最后测试相互连接可用

sqlplus sys/oracle@jyzhao as sysdba
sqlplus sys/oracle@jyzhaodg as sysdba

第二章 源数据库备份

vi backup.sh
备份脚本如下:

rman target / <<EOF
run {
allocate channel c1 device type disk;
allocate channel c2 device type disk;
backup as compressed backupset database filesperset 1 format '/u01/orabak/salehrdb_%d_%T_%s.bak';
backup current controlfile format '/u01/orabak/control.bak';
release channel c1;
release channel c2;
}
EOF

后台执行备份任务:

nohup sh backup.sh &

注意:如果使用backup as copy database format方案,就不用再备份到磁盘后再恢复了,可以节省时间。

backup as copy 方案备份脚本 backupcp.sh内容如下:

rman target / <<EOF
run {
allocate channel c1 device type disk;
allocate channel c2 device type disk;
backup as copy database format '+DATA/JYZHAODG/DATAFILE/%u.dbf';
release channel c1;
release channel c2;
}
EOF

注意:这种方式,路径包含的目录需手动创建。

mkdir +DATA/JYZHAODG/DATAFILE

第三章 参数文件

3.1 修改主库参数文件

确认当前环境ORACLE_SID:

echo $ORACLE_SID
export ORACLE_SID=jyzhao1

根据spfile文件创建pfile:

create pfile='/tmp/pfile.ora' from spfile;

Primary RAC 添加参数

--为不停止primary RAC,所以尽可能动态修改参数:
show parameter log_archive_config
show parameter db_file_name_convert
show parameter log_file_name_convert
show parameter fal_client
show parameter fal_server
show parameter log_archive_dest_3 alter system set log_archive_config='dg_config=(jyzhao,jyzhaodg)';
alter system set db_file_name_convert='+DATA/jyzhaodg','+DATA/jyzhao' scope=spfile;
alter system set log_file_name_convert='+DATA/jyzhaodg','+DATA/jyzhao' scope=spfile;
alter system set fal_client='jyzhao';
alter system set fal_server='jyzhaodg';
alter system set log_archive_dest_3='service=jyzhaodg valid_for=(online_logfiles,primary_role) db_unique_name=jyzhaodg';
--暂时defer传输链路,防止此时主库告警生成相关错误
SQL> alter system set log_archive_dest_state_3=defer;

3.2 修改Standby RAC 参数

根据主库之前导出的参数文件修改备库的参数文件:
cp /tmp/pfile.ora /tmp/pfile_std.ora
vi /tmp/pfile_std.ora

*._high_priority_processes='LMS*'
*.audit_file_dest='/u01/app/oracle/admin/jyzhaodg/adump'
*.audit_trail='db'
*.cluster_database=true
*.compatible='11.2.0.4.0'
*.control_files='+DATA/jyzhaodg/controlfile/current.260.931878631','+FRA/jyzhaodg/controlfile/current.256.931878631'
*.db_block_size=8192
*.db_create_file_dest='+DATA'
*.db_domain=''
*.db_name='jyzhao'
*.db_recovery_file_dest='+FRA'
*.db_recovery_file_dest_size=4621074432
*.diagnostic_dest='/u01/app/oracle'
*.dispatchers='(PROTOCOL=TCP) (SERVICE=jyzhaoXDB)'
jyzhaodg2.instance_number=2
jyzhaodg1.instance_number=1
*.log_archive_format='%t_%s_%r.dbf'
*.memory_target=313286272
*.open_cursors=300
*.processes=150
*.remote_listener='oradb-scan:1521'
*.remote_login_passwordfile='exclusive'
jyzhaodg2.thread=2
jyzhaodg1.thread=1
jyzhaodg2.undo_tablespace='UNDOTBS2'
jyzhaodg1.undo_tablespace='UNDOTBS1'
#add
db_unique_name='jyzhaodg'
log_archive_config='dg_config=(jyzhao,jyzhaodg)'#db_unique_name
db_file_name_convert='+DATA/jyzhao','+DATA/jyzhaodg'
log_file_name_convert='+DATA/jyzhao','+DATA/jyzhaodg'
standby_file_management=auto
fal_client='jyzhaodg'#tnsnames.ora
fal_server='jyzhao'#salehrdb
log_archive_dest_3='service=jyzhao valid_for=(online_logfiles,primary_role) db_unique_name=jyzhao'

主要是注意后面#add之后的内容。

3.3 在ASM中创建standby的spfile

在ASM中创建standby的spfile,并确定各节点的参数文件内容指向磁盘中的spfile。
节点1:

echo $ORACLE_SID
export ORACLE_SID=jyzhaodg1
create spfile='+DATA/jyzhaodg/spfilejyzhaodg.ora' from pfile='/tmp/pfile_std.ora';
--
cat initjyzhaodg1.ora
SPFILE='+DATA/jyzhaodg/spfilejyzhaodg.ora'

节点2:

echo $ORACLE_SID
export ORACLE_SID=jyzhaodg2
cat initjyzhaodg2.ora
SPFILE='+DATA/jyzhaodg/spfilejyzhaodg.ora'

创建adump目录(所有节点)

mkdir -p /u01/app/oracle/admin/jyzhaodg/adump

3.4 Standby RAC启动到nomount

节点1:

echo $ORACLE_SID
export ORACLE_SID=jyzhaodg1
startup nomount

节点2:

echo $ORACLE_SID
export ORACLE_SID=jyzhaodg2
startup nomount

第四章 rman恢复控制文件

在Primary RAC上创建备库使用的控制文件:

echo $ORACLE_SID
export ORACLE_SID=jyzhao1
SQL> alter database create standby controlfile as '/tmp/control01.ctlbak';

在Standby RAC的节点1上恢复控制文件并启动到mount:

echo $ORACLE_SID
export ORACLE_SID=jyzhaodg1 restore controlfile from '/tmp/control01.ctlbak';
alter database mount;
crosscheck backupset;
--如果是之前copy到磁盘组的备份没加载到控制文件中,可以手动catalog
catalog start with '+data/jyzhaodg/DATAFILE';
--同样,如果是之前的备份集没加载到控制文件中,一样手动catalog
catalog start with '/u01/orabak/';

查看此时standby记录的各文件路径是否符合预期:

SQL> select name from v$datafile;

NAME
--------------------------------------------------------------------------------
+DATA/jyzhaodg/datafile/system.256.931878537
+DATA/jyzhaodg/datafile/sysaux.257.931878537
+DATA/jyzhaodg/datafile/undotbs1.258.931878537
+DATA/jyzhaodg/datafile/users.259.931878537
+DATA/jyzhaodg/datafile/undotbs2.264.931878827
+DATA/jyzhaodg/datafile/dbs_d_jingyu.268.937515173 6 rows selected. SQL> select member from v$logfile; MEMBER
--------------------------------------------------------------------------------
+DATA/jyzhaodg/onlinelog/group_2.262.931878637
+FRA/jyzhao/onlinelog/group_2.258.931878639
+DATA/jyzhaodg/onlinelog/group_1.261.931878635
+FRA/jyzhao/onlinelog/group_1.257.931878637
+DATA/jyzhaodg/onlinelog/group_3.265.931879021
+FRA/jyzhao/onlinelog/group_3.259.931879023
+DATA/jyzhaodg/onlinelog/group_4.266.931879027
+FRA/jyzhao/onlinelog/group_4.260.931879029 8 rows selected. SQL> select name from v$tempfile; NAME
--------------------------------------------------------------------------------
+DATA/jyzhaodg/tempfile/temp.263.931878661 SQL> select name from v$controlfile; NAME
--------------------------------------------------------------------------------
+DATA/jyzhaodg/controlfile/current.288.937645851
+FRA/jyzhaodg/controlfile/current.275.937645851

发现日志文件有不符合预期的路径,进行修正:

SQL> show parameter convert

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_file_name_convert string +DATA/jyzhao, +DATA/jyzhaodg
log_file_name_convert string +DATA/jyzhao, +DATA/jyzhaodg SQL> alter system set log_file_name_convert='+DATA/jyzhao','+DATA/jyzhaodg','+FRA/jyzhao','+FRA/jyzhaodg' scope=spfile; SQL> shutdown immediate;
ORA-01109: database not open Database dismounted.
ORACLE instance shut down.
SQL> startup mount;
ORACLE instance started. Total System Global Area 313159680 bytes
Fixed Size 2252824 bytes
Variable Size 222302184 bytes
Database Buffers 83886080 bytes
Redo Buffers 4718592 bytes
Database mounted.
SQL> select member from v$logfile; MEMBER
--------------------------------------------------------------------------------
+DATA/jyzhaodg/onlinelog/group_2.262.931878637
+FRA/jyzhaodg/onlinelog/group_2.258.931878639
+DATA/jyzhaodg/onlinelog/group_1.261.931878635
+FRA/jyzhaodg/onlinelog/group_1.257.931878637
+DATA/jyzhaodg/onlinelog/group_3.265.931879021
+FRA/jyzhaodg/onlinelog/group_3.259.931879023
+DATA/jyzhaodg/onlinelog/group_4.266.931879027
+FRA/jyzhaodg/onlinelog/group_4.260.931879029 8 rows selected.

第五章 rman恢复数据库

Standby RAC节点1:

确定ORACLE_SID变量:

echo $ORACLE_SID
export ORACLE_SID=jyzhaodg1

a. 如果是使用从备份集恢复的方式

vi restore.sh

rman target / <<EOF! > db_restore.log
run {
allocate channel d1 type disk;
allocate channel d2 type disk;
restore database;
release channel d1;
release channel d2;
}
exit;
EOF!

nohup sh restore.sh &

b. 如果是直接使用copy到磁盘组的

直接switch database to copy即可。

RMAN> switch database to copy;

using target database control file instead of recovery catalog
datafile 1 switched to datafile copy "+DATA/jyzhaodg/datafile/0eru6m4s.dbf"
datafile 2 switched to datafile copy "+DATA/jyzhaodg/datafile/0fru6m4s.dbf"
datafile 3 switched to datafile copy "+DATA/jyzhaodg/datafile/0hru6meo.dbf"
datafile 4 switched to datafile copy "+DATA/jyzhaodg/datafile/0iru6mg5.dbf"
datafile 5 switched to datafile copy "+DATA/jyzhaodg/datafile/0jru6mg6.dbf"
datafile 6 switched to datafile copy "+DATA/jyzhaodg/datafile/0gru6men.dbf"

第六章 备库开启日志应用

确认Primary RAC的日志传输链路打开:

echo $ORACLE_SID
export ORACLE_SID=jyzhao1 SQL> alter system set log_archive_dest_state_3=enable;

Standby RAC节点1在mount状态下开启日志应用:

echo $ORACLE_SID
export ORACLE_SID=jyzhaodg1 SQL> alter database recover managed standby database disconnect from session;

第七章 创建standby log

停止备库应用:

SQL> alter database recover managed standby database cancel;

查看日志信息:

SQL> select * from v$Log;

    GROUP#    THREAD#  SEQUENCE#      BYTES  BLOCKSIZE    MEMBERS ARC STATUS           FIRST_CHANGE# FIRST_TIME   NEXT_CHANGE# NEXT_TIME
---------- ---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- ------------ ------------ ------------
1 1 69 52428800 512 2 YES CURRENT 2450934 03-MAR-17 2.8147E+14
2 1 0 52428800 512 2 YES UNUSED 2440706 03-MAR-17 2450934 03-MAR-17
3 2 0 52428800 512 2 YES UNUSED 2440817 03-MAR-17 2450939 03-MAR-17
4 2 36 52428800 512 2 YES CURRENT 2450939 03-MAR-17 2.8147E+14 SQL> col member for a70
SQL> select group#, type, member from v$logfile; GROUP# TYPE MEMBER
---------- ------- ----------------------------------------------------------------------
2 ONLINE +DATA/jyzhaodg/onlinelog/group_2.298.937648563
2 ONLINE +FRA/jyzhaodg/onlinelog/group_2.278.937648565
1 ONLINE +DATA/jyzhaodg/onlinelog/group_1.297.937648559
1 ONLINE +FRA/jyzhaodg/onlinelog/group_1.279.937648561
3 ONLINE +DATA/jyzhaodg/onlinelog/group_3.299.937648567
3 ONLINE +FRA/jyzhaodg/onlinelog/group_3.389.937648569
4 ONLINE +DATA/jyzhaodg/onlinelog/group_4.300.937648573
4 ONLINE +FRA/jyzhaodg/onlinelog/group_4.390.937648573 8 rows selected.

根据检查结果,合理为数据库添加standby logfile:

alter database add standby logfile thread 1 group 11 ('+DATA','+FRA') size 52428800;
alter database add standby logfile thread 1 group 12 ('+DATA','+FRA') size 52428800;
alter database add standby logfile thread 1 group 13 ('+DATA','+FRA') size 52428800; alter database add standby logfile thread 2 group 21 ('+DATA','+FRA') size 52428800;
alter database add standby logfile thread 2 group 22 ('+DATA','+FRA') size 52428800;
alter database add standby logfile thread 2 group 23 ('+DATA','+FRA') size 52428800;

添加完再次查看:

SQL> select group#, type, member from v$logfile;

    GROUP# TYPE    MEMBER
---------- ------- ----------------------------------------------------------------------
2 ONLINE +DATA/jyzhaodg/onlinelog/group_2.298.937648563
2 ONLINE +FRA/jyzhaodg/onlinelog/group_2.278.937648565
1 ONLINE +DATA/jyzhaodg/onlinelog/group_1.297.937648559
1 ONLINE +FRA/jyzhaodg/onlinelog/group_1.279.937648561
3 ONLINE +DATA/jyzhaodg/onlinelog/group_3.299.937648567
3 ONLINE +FRA/jyzhaodg/onlinelog/group_3.389.937648569
4 ONLINE +DATA/jyzhaodg/onlinelog/group_4.300.937648573
4 ONLINE +FRA/jyzhaodg/onlinelog/group_4.390.937648573
11 STANDBY +DATA/jyzhaodg/onlinelog/group_11.301.937648773
11 STANDBY +FRA/jyzhaodg/onlinelog/group_11.391.937648775
12 STANDBY +DATA/jyzhaodg/onlinelog/group_12.302.937648777 GROUP# TYPE MEMBER
---------- ------- ----------------------------------------------------------------------
12 STANDBY +FRA/jyzhaodg/onlinelog/group_12.392.937648779
13 STANDBY +DATA/jyzhaodg/onlinelog/group_13.303.937648779
13 STANDBY +FRA/jyzhaodg/onlinelog/group_13.393.937648781
21 STANDBY +DATA/jyzhaodg/onlinelog/group_21.304.937648783
21 STANDBY +FRA/jyzhaodg/onlinelog/group_21.394.937648783
22 STANDBY +DATA/jyzhaodg/onlinelog/group_22.305.937648785
22 STANDBY +FRA/jyzhaodg/onlinelog/group_22.395.937648787
23 STANDBY +DATA/jyzhaodg/onlinelog/group_23.306.937648787
23 STANDBY +FRA/jyzhaodg/onlinelog/group_23.396.937648789 20 rows selected.

继续开启备库应用,确定恢复完成日志没报错信息后取消日志应用,打开数据库,开启ADG:

alter database recover managed standby database disconnect from session;
alter database recover managed standby database cancel;
alter database open;
alter database recover managed standby database using current logfile disconnect from session;

查看DG同步状态:

SQL> SELECT OPEN_MODE, DATABASE_ROLE, SWITCHOVER_STATUS, FORCE_LOGGING, DATAGUARD_BROKER, GUARD_STATUS FROM V$DATABASE; 

OPEN_MODE            DATABASE_ROLE    SWITCHOVER_STATUS    FOR DATAGUAR GUARD_S
-------------------- ---------------- -------------------- --- -------- -------
READ ONLY WITH APPLY PHYSICAL STANDBY NOT ALLOWED NO DISABLED NONE SQL> set lines 1000
SQL> select * from v$dataguard_stats; NAME VALUE UNIT TIME_COMPUTED DATUM_TIME
-------------------------------- ---------------------------------------------------------------- ------------------------------ ------------------------------ ------------------------------
transport lag +00 00:09:37 day(2) to second(0) interval 03/03/2017 10:03:20 03/03/2017 10:03:13
apply lag +00 00:09:38 day(2) to second(0) interval 03/03/2017 10:03:20 03/03/2017 10:03:13
apply finish time day(2) to second(3) interval 03/03/2017 10:03:20
estimated startup time 40 second 03/03/2017 10:03:20 --可以在Primary RAC上归档当前日志模拟业务切换归档:
SQL> SELECT OPEN_MODE, DATABASE_ROLE, SWITCHOVER_STATUS, FORCE_LOGGING, DATAGUARD_BROKER, GUARD_STATUS FROM V$DATABASE; OPEN_MODE DATABASE_ROLE SWITCHOVER_STATUS FOR DATAGUAR GUARD_S
-------------------- ---------------- -------------------- --- -------- -------
READ WRITE PRIMARY TO STANDBY NO DISABLED NONE SQL> alter system archive log current; System altered. --再次在Standby RAC上查看DG同步状态:
SQL> r
1* select * from v$dataguard_stats NAME VALUE UNIT TIME_COMPUTED DATUM_TIME
-------------------------------- ---------------------------------------------------------------- ------------------------------ ------------------------------ ------------------------------
transport lag +00 00:00:00 day(2) to second(0) interval 03/03/2017 10:04:45 03/03/2017 10:04:44
apply lag +00 00:00:00 day(2) to second(0) interval 03/03/2017 10:04:45 03/03/2017 10:04:44
apply finish time day(2) to second(3) interval 03/03/2017 10:04:45
estimated startup time 40 second 03/03/2017 10:04:45

至此,已完成RAC Standby库在同环境下的创建。

第八章 检查资源状态

我们可以将RAC Standby也加入到crs资源中:

[oracle@oradb23 ~]$ srvctl add database -d jyzhaodg -o $ORACLE_HOME -i jyzhaodg1 -n jyzhao
[oracle@oradb23 ~]$ srvctl add instance -d jyzhaodg -i jyzhaodg1 -n oradb23
[oracle@oradb23 ~]$ srvctl add instance -d jyzhaodg -i jyzhaodg2 -n oradb24
--启动数据库
[oracle@oradb23 ~]$ srvctl start database -d salehrdg
--查看资源状态:
[grid@oradb23 ~]$ crsctl stat res -t

总结:同环境下搭建Standby RAC,最重要的注意事项就是一定要细心,操作前确保自己操作的是正确的ORACLE_SID,备库的路径也要反复确认无误再操作。

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