How To Configure Server Side Transparent Application Failover (文档 ID 460982.1)

710661809

　　In this Document
　　APPLIES TO:
　　Oracle Database - Enterprise Edition
　　Information in this document applies to any platform.
GOAL
　　How to configure Server Side Transparent Application Failover (TAF)?
　　Server side TAF settings override client-side counterparts that might be configured in TNS connect descriptors. If TAF is not configured on the client side, then at a minimum, the failover type must be set to enable TAF. If the failover type is set on the server side, then the failover method will default to BASIC. Delay and retries are optional and may be specified independently.
SOLUTION
　　1. Create a service on the RAC cluster to setup for TAF. Example creates a service called server_taf to the database called rac, with instance names rac1 & rac2.

　　Please note for the service name, select a name that is unique and not the same as the default service name created. A special Oracle database service is created by default for your Oracle RAC database. This default service is always available on all instances in an Oracle RAC environment, unless an instance is in restricted mode. You cannot>　　srvctl add service -d rac -s server_taf -r "rac1,rac2" -P BASIC
　　2. Start the service server_taf
　　srvctl start service -d rac -s server_taf
　　3. Check service is running
　　srvctl config service -d rac
　　ractest PREF: rac1 rac2 AVAIL:
　　server_taf PREF: rac1 rac2 AVAIL:
　　4. Find the service_id value for the service just created
　　sqlplus /nolog
　　Connect / as sysdba
　　SQL> select name,service_id from dba_services where name = 'server_taf';
　　NAME                                                             SERVICE_ID
　　---------------------------------------------------------------- ----------
　　server_taf                                                                6
　　5. Review the standard setup for the services
　　SQL>col name format a15
　　col failover_method format a11 heading 'METHOD'
　　col failover_type format a10 heading 'TYPE'
　　col failover_retries format 9999999 heading 'RETRIES'
　　col goal format a10
　　col clb_goal format a8
　　col AQ_HA_NOTIFICATIONS format a5 heading 'AQNOT'
　　SQL>select name, failover_method, failover_type, failover_retries,goal, clb_goal,aq_ha_notifications
　　from dba_services where service_id = 6
　　NAME            METHOD      TYPE       RETRIES  GOAL       CLB_GOAL AQNOT
　　--------------- ----------- ---------- -------- ---------- -------- -----
　　server_taf                                                 LONG     NO
　　Please note there is no values for method, type or retries. These are required todo server side TAF.

　　The cause of this problem has been>　　6. Add the server side failover parameters to the service. (Pre 11.2)
　　Server side TAF method is BASIC. BASIC is the only value currently supported. This means that a new connection is established at failure time. It is not possible to pre-establish a backup connection. (which is to say, PRECONNECT is not supported)
　　SQL> execute dbms_service.modify_service (service_name => 'server_taf' -
　　, aq_ha_notifications => true -
　　, failover_method => dbms_service.failover_method_basic -
　　, failover_type => dbms_service.failover_type_select -
　　, failover_retries => 180 -
　　, failover_delay => 5 -
　　, clb_goal => dbms_service.clb_goal_long);
　　PL/SQL procedure successfully completed.

　　Addtional failover parameters value can be found in the Oracle Database PL/SQL Packages and Types Reference 11g>　　For 11.2 version use SVRCTL to modify the service
　　srvctl modify service -d RAC -s server_taf -m BASIC -e SELECT -q TRUE -j LONG
　　Service can be checked with the command:
　　srvctl config service -d RAC
　　Service name: server_taf
　　Service is enabled
　　Server pool: RAC_server_taf
　　Cardinality: 2
　　Disconnect: false
　　Service role: PRIMARY
　　Management policy: AUTOMATIC
　　DTP transaction: false
　　AQ HA notifications: true
　　Failover type: SELECT
　　Failover method: BASIC
　　TAF failover retries: 0
　　TAF failover delay: 0
　　Connection Load Balancing Goal: LONG
　　Runtime Load Balancing Goal: NONE
　　TAF policy specification: BASIC
　　Edition:
　　Preferred instances: RAC1,RAC2
　　Available instances:
　　7. Check the service and we can now see values for Method, Type and Retries.
　　SQL>select name, failover_method, failover_type, failover_retries,goal, clb_goal,aq_ha_notifications
　　from dba_services where service_id = 6
　　NAME            METHOD      TYPE        RETRIES GOAL       CLB_GOAL AQNOT
　　--------------- ----------- ---------- -------- ---------- -------- -----
　　server_taf      BASIC       SELECT          180 NONE       LONG     YES
　　8. Check the listener has the service registered. (output will look similar too following, depending on version used)
　　lsnrctl services
　　Service "server_taf.za.oracle.com" has 2 instance(s).
　　Instance "rac1", status READY, has 2 handler(s) for this service...
　　Handler(s):
　　"DEDICATED" established:0 refused:0 state:ready
　　REMOTE SERVER
　　(ADDRESS=(PROTOCOL=TCP)(HOST=dell01)(PORT=1521))
　　"DEDICATED" established:0 refused:0 state:ready
　　LOCAL SERVER
　　Instance "rac2", status READY, has 1 handler(s) for this service...
　　Handler(s):
　　"DEDICATED" established:0 refused:0 state:ready
　　REMOTE SERVER
　　(ADDRESS=(PROTOCOL=TCP)(HOST=dell02)(PORT=1521))
　　9. Create a net service name. Here we have client load balancing between the two nodes.
　　SERVERTAF =
　　(DESCRIPTION =
　　(LOAD_BALANCE = yes)
　　(ADDRESS = (PROTOCOL = TCP)(HOST = dell01)(PORT = 1521))
　　(ADDRESS = (PROTOCOL = TCP)(HOST = dell02)(PORT = 1521))
　　(CONNECT_DATA =
　　(SERVICE_NAME = server_taf.za.oracle.com)
　　)
　　)
　　10. Testing...
　　SQL*Plus: Release 10.2.0.1.0 - Production on Tue Oct 2 12:15:44 2007
　　Copyright (c) 1982, 2005, Oracle.  All rights reserved.
　　Connected to:
　　Oracle Database 10g Enterprise Edition Release 10.2.0.3.0 - Production
　　With the Partitioning, Real Application Clusters, OLAP and Data Mining options
　　SQL> select host_name,instance_name from v$instance;
　　HOST_NAME
　　----------------------------------------------------------------
　　INSTANCE_NAME
　　----------------
　　dell02
　　rac2
　　11. Shutdown the database in the node the connection has routed to
　　SQL> select instance_name from V$instance;
　　INSTANCE_NAME
　　----------------
　　rac2
　　SQL> shutdown abort;
　　ORACLE instance shut down.
　　12. TAF will now kick in
　　SQL> /
　　HOST_NAME
　　----------------------------------------------------------------
　　INSTANCE_NAME
　　----------------
　　dell01
　　rac1
　　Oracle Net client trace of sqlplus connection during failover shows :
　　Shows the calling net service name
　　[02-OCT-2007 12:15:44:618] niotns: Calling address: (DESCRIPTION=(LOAD_BALANCE=yes)(ADDRESS=(PROTOCOL=TCP)(HOST=dell01)(PORT=1521))
　　(ADDRESS=(PROTOCOL=TCP)(HOST=dell02)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=server_taf.za.oracle.com)
　　(CID=(PROGRAM=d:\oracle\102ee\bin\sqlplus.exe)(HOST=sflood-uk2)(USER=sflood))))
　　Selected node dell02
　　[02-OCT-2007 12:15:44:648] nttbnd2addr: looking up IP addr for host: dell02
　　Connection handshake
　　[02-OCT-2007 12:15:44:878] nscon: sending NSPTCN packet
　　[02-OCT-2007 12:15:45:229] nscon: got NSPTRS packet
　　[02-OCT-2007 12:15:45:229] nscon: sending NSPTCN packet
　　[02-OCT-2007 12:15:45:429] nscon: got NSPTAC packet
　　The select running
　　[02-OCT-2007 12:16:04:046] nspsend: 00 00 00 00 00 E8 64 0B |......d.|
　　[02-OCT-2007 12:16:04:046] nspsend: 01 2E 73 65 6C 65 63 74 |..select|
　　[02-OCT-2007 12:16:04:046] nspsend: 20 68 6F 73 74 5F 6E 61 |.host_na|
　　[02-OCT-2007 12:16:04:046] nspsend: 6D 65 2C 69 6E 73 74 61 |me,insta|
　　[02-OCT-2007 12:16:04:046] nspsend: 6E 63 65 5F 6E 61 6D 65 |nce_name|
　　[02-OCT-2007 12:16:04:046] nspsend: 20 66 72 6F 6D 20 76 24 |.from.v$|
　　[02-OCT-2007 12:16:04:046] nspsend: 69 6E 73 74 61 6E 63 65 |instance|
　　Here the the time the instance was shutdown
　　[02-OCT-2007 12:16:05:077] nioqrc: exit
　　[02-OCT-2007 12:18:20:642] nioqsn: entry
　　Select attempts to run again
　　[02-OCT-2007 12:18:20:652] nspsend: 00 00 00 00 00 E8 64 0B |......d.|
　　[02-OCT-2007 12:18:20:652] nspsend: 01 2E 73 65 6C 65 63 74 |..select|
　　[02-OCT-2007 12:18:20:652] nspsend: 20 68 6F 73 74 5F 6E 61 |.host_na|
　　[02-OCT-2007 12:18:20:652] nspsend: 6D 65 2C 69 6E 73 74 61 |me,insta|
　　[02-OCT-2007 12:18:20:652] nspsend: 6E 63 65 5F 6E 61 6D 65 |nce_name|
　　[02-OCT-2007 12:18:20:652] nspsend: 20 66 72 6F 6D 20 76 24 |.from.v$|
　　[02-OCT-2007 12:18:20:652] nspsend: 69 6E 73 74 61 6E 63 65 |instance|
　　Fails, due to instance was shutdown

　　[02-OCT-2007 12:18:20:652] nserror: nsres:>　　[02-OCT-2007 12:18:20:652] nsrdr: error exit
　　[02-OCT-2007 12:18:20:652] nsdo: nsctxrnk=0
　　[02-OCT-2007 12:18:20:652] nsdo: error exit
　　[02-OCT-2007 12:18:20:652] nioqer: entry
　　[02-OCT-2007 12:18:20:652] nioqer: incoming err = 12151
　　[02-OCT-2007 12:18:20:652] nioqce: entry
　　[02-OCT-2007 12:18:20:652] nioqce: exit
　　[02-OCT-2007 12:18:20:652] nioqer: returning err = 3113
　　TAF kicks in
　　[02-OCT-2007 12:18:20:652] nsc2addr: (DESCRIPTION=(LOAD_BALANCE=yes)(ADDRESS=(PROTOCOL=TCP)(HOST=dell01)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=server_taf.za.oracle.com)(CID=(PROGRAM=d:\oracle\102ee\bin\sqlplus.exe)(HOST=sflood-uk2)(USER=sflood))))
　　Connection fails over to node dell01
　　[02-OCT-2007 12:18:20:652] nttbnd2addr: looking up IP addr for host: dell01
　　Connection handshake is completed
　　[02-OCT-2007 12:18:20:863] nscon: sending NSPTCN packet
　　[02-OCT-2007 12:18:23:547] nscon: got NSPTRS packet
　　[02-OCT-2007 12:18:23:547] nscon: sending NSPTCN packet
　　[02-OCT-2007 12:18:23:747] nscon: got NSPTAC packet
　　Select is run
　　[02-OCT-2007 12:18:47:861] nspsend: 00 00 00 00 00 E8 64 0B |......d.|
　　[02-OCT-2007 12:18:47:861] nspsend: 01 2E 73 65 6C 65 63 74 |..select|
　　[02-OCT-2007 12:18:47:861] nspsend: 20 68 6F 73 74 5F 6E 61 |.host_na|
　　[02-OCT-2007 12:18:47:861] nspsend: 6D 65 2C 69 6E 73 74 61 |me,insta|
　　[02-OCT-2007 12:18:47:861] nspsend: 6E 63 65 5F 6E 61 6D 65 |nce_name|
　　[02-OCT-2007 12:18:47:861] nspsend: 20 66 72 6F 6D 20 76 24 |.from.v$|
　　[02-OCT-2007 12:18:47:861] nspsend: 69 6E 73 74 61 6E 63 65 |instance|