oracle 10g RAC Failover(三)

原创黄宸宁 2013-04-17

1117

oracle 10g RAC Failover(一)

oracle 10g RAC Failover(二)

二、TAF（Transparent Application Failover）

1、配置客户端tnsnames.ora，首先测试TYPE为session的情况

orcldb =
  (DESCRIPTION =
     (ADDRESS = (PROTOCOL = TCP)(HOST = orlrac1-vip)(PORT = 1521))
     (ADDRESS = (PROTOCOL = TCP)(HOST = orlrac2-vip)(PORT = 1521))
      (LOAD_BALANCE=YES)
      (CONNECT_DATA=
	(SERVER = DEDICATED)
	(SERVICE_NAME = orcldb)
	(FAILOVER_MODE=
		(TYPE=session)
		(METHOD=basic)
		(RETRIES=180)
		(DELAY=5)
	)
   )

2、通过脚本进行测试

[oracle@hcn10g script]$ cat loginfail1.sh
sqlplus -s scott/oracle@orcldb <<EOF>fail.log
select instance_name from v$instance
/
select object_name,object_id from dba_objects
/
select instance_name from v$instance
/
exit
EOF

在运行脚本的过程中，对1号节点执行shutdown abort操作，模拟断电

运行结果：

[oracle@hcn10g script]$ 
[oracle@hcn10g script]$ ksh loginfail1.sh
[oracle@hcn10g script]$ 
[oracle@hcn10g script]$ 
[oracle@hcn10g script]$ cat fail.log|head -5

INSTANCE_NAME
----------------
orcldb1

[oracle@hcn10g script]$ 
[oracle@hcn10g script]$ cat fail.log|tail -5   ---在关闭1号节点后，连接自动切换到2号节点

INSTANCE_NAME
----------------
orcldb2

[oracle@hcn10g script]$ 
[oracle@hcn10g script]$ cat fail.log|grep ORA-   
ORA-25401: can not continue fetches
[oracle@hcn10g script]$ 

---有ORA-的提示，在报错的同时该连接已经重新连接到其他可用的数据库实例上，后续的SQL语句不受影响。
---但当前这条SQL将不会继续执行

[oracle@hcn10g script]$ 
[oracle@hcn10g script]$ cat fail.log|wc -l   
37226
[oracle@hcn10g script]$ 

---当1号实例abort后，虽然会自动连接到其他正常的节点上，不过正在执行的SQL将中断，后续的SQL会继续执行

OBJECT_NAME                               OBJECT_ID
---------------------------------------- ----------
sun/security/x509/X509CRLImpl                 33972
java/security/cert/CRL                        20087
java/security/cert/CRL                        33973
sun/security/pkcs/PKCS7                       20088
sun/security/pkcs/PKCS7                       33974
/8f9b31a0_ExceptionInInitializ                20089
/8f9b31a0_ExceptionInInitializ                33975
/f41eb3e7_PKCS9Attribute                      20090
ERROR:
ORA-25401: can not continue fetches       ----当前的SQL中断
29235 rows selected.

INSTANCE_NAME                             ----后续SQL继续进行
----------------
orcldb2

3、修改tnsnames.ora，测试TYPE为SELECT的情况

ORCLDB =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.100.112)(PORT = 1521))
    (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.100.114)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcldb)
      (FAILOVER_MODE=
	(TYPE=SELECT)
	(METHOD=basic)
	(RETRIES=180)
	(DELAY=5)
       )
    )
  )

4、通过脚本进行测试
在运行脚本的过程中，对1号节点执行shutdown abort操作，模拟断电

[oracle@hcn10g script]$ cat loginfail1.sh
sqlplus -s scott/oracle@orcldb <<EOF>fail.log
select instance_name from v$instance
/
select object_name,object_id from dba_objects
/
select instance_name from v$instance
/
exit
EOF
[oracle@hcn10g script]$ 

[oracle@hcn10g script]$ 
[oracle@hcn10g script]$ ksh loginfail1.sh
[oracle@hcn10g script]$ 
[oracle@hcn10g script]$ 
[oracle@hcn10g script]$ cat fail.log |head -5

INSTANCE_NAME
----------------
orcldb1

[oracle@hcn10g script]$ 
[oracle@hcn10g script]$ cat fail.log|tail -5   ---在关闭1号节点后，连接自动切换到2号节点

INSTANCE_NAME
----------------
orcldb2

[oracle@hcn10g script]$ 
[oracle@hcn10g script]$ cat fail.log|grep ORA-
[oracle@hcn10g script]$ 
[oracle@hcn10g script]$ 
[oracle@hcn10g script]$ 
[oracle@hcn10g script]$ cat fail.log|wc -l
63727
[oracle@hcn10g script]$

没有出现ORA-的报错
如果直接输出的话，可以在节点1中断过程中，
看到输出结果在短暂的停顿后重新恢复输出，但是不会有报错

oracle

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oracle 10g RAC Failover(三)

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