Oracle 19C 配置TAF
Oracle 19C 配置TAF
- 一、客户端配置TAF
- 二、数据库服务端TAF配置
- 三、服务切换测试
- 四、Oracle用户查看服务
一、客户端配置TAF
示例：
##在客户端tnsnames.ora文件中添加如下配置：
Lemon =(DESCRIPTION =(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.127.104)(PORT = 1521))(CONNECT_DATA =(SERVER=DEDICATED)(SERVICE_NAME = mesdb)(FAILOVER_MODE=(TYPE=session)(METHOD=basic)(RETRIES=180)(DELAY=5))))
选项含义解释：
TYPE：故障转移类型。定义故障转移后会话的重建方式。
| 选项 | 含义 |
|---|---|
session | 会话级故障转移（常用）： - 连接中断时，在备用节点重建新会话。 - 用户需重新执行未提交的事务（SELECT查询自动恢复）。 |
select | 查询级故障转移（高级）： - 在游标打开期间发生故障，自动在新节点恢复结果集。 - 限制：仅支持 SELECT，且游标需以WITH HOLD方式打开（如JDBC ResultSet.HOLD_CURSORS_OVER_COMMIT）。 |
none | 禁用故障转移（默认值）。 |
推荐：普通应用用
session；只读报表系统可尝试select（需应用适配游标）。
METHOD：故障转移触发方式。定义何时建立到备用节点的连接。
| 选项 | 含义 |
|---|---|
basic | 被动等待故障（默认）： - 主节点故障后才尝试连接备用节点。 - 优点：节省资源。 - 缺点：切换延迟较高（需重建TCP连接）。 |
preconnect | 预先连接备用节点： - 初次连接时同时连接主备节点（备用节点待命）。 - 优点：故障转移秒级完成（会话状态提前同步）。 - 缺点：双倍连接数消耗资源。 |
推荐：高延迟敏感系统用
preconnect（评估资源开销）；普通场景用basic。
RETRIES：重试次数
| 参数 | 含义 | 默认值 |
|---|---|---|
RETRIES | 连接失败后的最大重试次数（整数）。 | 5 |
DELAY：重试间隔
| 参数 | 含义 | 默认值 |
|---|---|---|
DELAY | 每次重试的间隔时间（秒）。 | 1 |
重试行为： 客户端每间隔DELAY秒重试一次，最多尝试RETRIES次。
示例：(RETRIES=180, DELAY=5) → 每5秒重试一次，持续15分钟（180×5=900秒）。
⚠️ 注意：
- 若
RETRIES=0或未设置，则不会重试（立即报错）。- 过长重试可能导致应用线程阻塞，需结合应用超时机制使用。
点击跳转，可见官方文档说明
二、数据库服务端TAF配置
示例：
##Oracle-11G
1）添加SERVICE--oratest
srvctl add service -d lemon -s oratest -r lemon1 -a lemon2 -P basic -e session -w 5 -z 3 -y automatic##语法说明：
-d：数据库名称
-s：新创建的service名称
-r：首选节点列表
-a：备用节点列表
-P：TAF策略
-e：TAF类型
-z：在failover之前重新尝试连接的次数
-w：在failover之前两次尝试连接的时间间隔
-y：是否自动启动2）启动SERVICE（添加完成后需手动启动）
srvctl start service -d lemon -s oratest
3）检查SERVICE信息
srvctl config service -d lemon -s oratest
4）停止SERVICE
srvctl stop service -d lemon -s oratest
5）移除SERVICE
srvctl remove service -d lemon -s oratest
##Oracle-19C
创建语法：
srvctl add service -database db_unique_name -service service_name_list
[-pdb pluggable_database] [-eval]
[-preferred preferred_list] [-available available_list] [-failback {YES | NO}]
[-netnum network_number] [-tafpolicy {BASIC | NONE}]
[-edition edition_name]
[-role "[PRIMARY][,PHYSICAL_STANDBY][,LOGICAL_STANDBY][,SNAPSHOT_STANDBY]"
[-policy {AUTOMATIC | MANUAL}] [-notification {TRUE | FALSE}]
[-clbgoal {SHORT | LONG}] [-failovertype {NONE|SESSION|SELECT|TRANSACTION|AUTO}]
[-rlbgoal {NONE | SERVICE_TIME | THROUGHPUT}] [-dtp {TRUE | FALSE}]
[-failovermethod {NONE | BASIC}] [-failoverretry failover_retries]
[-drain_timeout timeout] [-stopoption {NONE|IMMEDIATE|TRANSACTIONAL}]
[-failover_restore {NONE|LEVEL1|AUTO}] [-failoverdelay failover_delay]
[-sql_translation_profile sql_translation_profile]
[-global {TRUE | FALSE}] [-maxlag max_lag_time] [-commit_outcome {TRUE|FALSE}]
[-retention retention_time] [-replay_init_time replay_initiation_time]
[-session_state {STATIC|DYNAMIC|AUTO}] [-force] [-verbose]创建示例：1）添加SERVICE--oratest
srvctl add service -db lemon -service oratest -preferred "lemon1" -available "lemon2" -tafpolicy basic -failovertype SESSION -failoverdelay 5 -failoverretry 3 -policy AUTOMATIC2）启动SERVICE（添加完成后需手动启动）
srvctl start service -d lemon -s oratest
3）检查SERVICE信息
srvctl config service -d lemon -s oratest
5）停止SERVICE
srvctl stop service -d lemon -s oratest
5）移除SERVICE
srvctl remove service -d lemon -s oratest
虽然第一部分是11G的语法，但是在19C环境测试也是一样可以添加成功！！
点击跳转，可见官方文档说明
另附所有的参数详解
| Parameter | Description |
|---|---|
-db db_unique_name | Unique name for the database. |
-service service_name_list | Unique service name(s) within the cluster (comma-delimited). DB_DOMAIN appended if no domain specified. 4KB total length limit for all service names. |
-eval | Hypothetically evaluate command impact (only for policy-managed services). |
-edition edition_name | Initial session edition for connections (SRVCTL does not validate; user requires USE privilege). |
-sql_translation_profile profile_name | Specify SQL translation profile for migrated non-Oracle applications (use srvctl config service to view). |
-preferred preferred_list | Preferred instances for administrator-managed databases (mutually exclusive with -available; Oracle RAC only). |
-available available_list | Failover instances for administrator-managed databases (mutually exclusive with -preferred; Oracle RAC only). |
-failback {YES | NO} | Automatically fail back to preferred instances when available after failover. |
-serverpool server_pool | Server pool name for policy-managed databases (Oracle RAC only). |
-cardinality {UNIFORM | SINGLETON} | Service cardinality: UNIFORM (all instances) or SINGLETON (one instance). Policy-managed/Oracle RAC One Node only. |
-netnum network_number | Network number for service VIP dependency (default from -defaultnetwork database config; Oracle RAC/RAC One Node only). |
-tafpolicy {BASIC | NONE} | TAF policy specification (administrator-managed databases only). |
-role "[PRIMARY][,PHYSICAL_STANDBY][,LOGICAL_STANDBY][,SNAPSHOT_STANDBY]" | Service role(s) for automatic startup (matches Data Guard role; manual start unaffected). |
-policy {AUTOMATIC | MANUAL} | Service restart policy: AUTOMATIC (default, subject to role) or MANUAL (never auto-restarts). |
-notification {TRUE | FALSE} | Enable Fast Application Notification (FAN) for OCI connections. |
-rfpool pool_name | Reader farm server pool name. |
-dtp {TRUE | FALSE} | Enable Distributed Transaction Processing (Oracle RAC only; requires singleton/preferred single-node service). |
-clbgoal {SHORT | LONG} | Connection Load Balancing Goal: SHORT (runtime/integrated pools) or LONG (long-running sessions). |
-rlbgoal {NONE | SERVICE_TIME | THROUGHPUT} | Runtime Load Balancing Goal: SERVICE_TIME (response time) or THROUGHPUT (throughput). |
-failovertype {NONE | SESSION | SELECT | TRANSACTION | AUTO} | Failover type: TRANSACTION (Application Continuity), AUTO (Transparent App Continuity), SELECT/SESSION (TAF). |
-failovermethod {NONE | BASIC} | TAF failover method (backward compatibility; Oracle RAC only). |
-failoverretry failover_retries | Connection attempts after incident (Application Continuity/TAF). |
-drain_timeout timeout | Time (seconds) for resource draining during maintenance (default: unset; 0 = immediate). |
-stopoption {NONE | IMMEDIATE | TRANSACTIONAL} | Service stop mode: IMMEDIATE (drain sessions), TRANSACTIONAL (drain + timeout terminate). Requires -force. |
-failover_restore {NONE | LEVEL1 | AUTO} | Session state restore: LEVEL1 (AC/TAF), AUTO (Transparent AC). |
-failoverdelay failover_delay | Delay (seconds) between reconnect attempts (Application Continuity/TAF). |
-gsmflags gsm_flags | Set locality/region failover values. |
-pdb pluggable_database | Associate service with a PDB (SRVCTL does not validate PDB existence). |
-global {TRUE | FALSE} | Indicate Global Data Services service (GDS only). |
-maxlag maximum_lag_time | Maximum replication lag (seconds; default: ANY). |
-commit_outcome {TRUE | FALSE} | Enable Transaction Guard (commit outcome tracking). Required for -failovertype TRANSACTION. |
-retention retention_time | Commit outcome retention time (seconds) if -commit_outcome TRUE. |
-replay_init_time replay_initialization_time | Max time difference (seconds) for replay readiness (Application Continuity; default: 300). |
-session_state {STATIC | DYNAMIC | AUTO} | Non-transactional session state handling for AC/TAC. Requires -failovertype TRANSACTION/AUTO. |
-pqservice pq_service | Parallel query service name. |
-pqpool pq_pool | Parallel query server pool. |
-update {-preferred new_preferred_instance | -available new_available_instance} | Add instance to preferred/available lists. |
-css_critical {yes | no} | Weight service as critical for node eviction priority (administrator-managed only). |
-verbose | Display verbose output. |
-force | Force operation without listener configuration. |
添加完成
⚠️ 注意：
- 服务端创建成功后，客户端需要更新tns信息，用新的service连接：
三、服务切换测试
关闭节点一集群服务：
[root@lemon01 ~]# /u01/app/19.3.0/grid/bin/crsctl stop cluster -n lemon01
服务切换至节点二：
开启节点一集群服务：
[root@lemon01 ~]# /u01/app/19.3.0/grid/bin/crsctl start cluster -n lemon01
关闭节点二集群后，服务又在节点一online：
四、Oracle用户查看服务
##在数据库中查询配置的oratest的服务的详细信息
col name for a20
col FAILOVER_METHOD for a20
col FAILOVER_TYPE for a20
select SERVICE_ID,NAME,CREATION_DATE,FAILOVER_METHOD,FAILOVER_TYPE,FAILOVER_RETRIES,FAILOVER_DELAY,goal,clb_goal,aq_ha_notifications from dba_services where NAME='oratest';
##查看RAC环境中所有可被客户端连接的有效服务的相关信息
set line 222 pages 2222
col NETWORK_NAME for a30
col name for a18
col NETWORK_NAME for a30
col SESSION_STATE_CONSISTENCY for a30
col FAILOVER_RESTORE for a15
select inst_id,SERVICE_ID,NAME,NETWORK_NAME,CREATION_DATE,GOAL,GLOBAL,SESSION_STATE_CONSISTENCY,FAILOVER_RESTORE from gv$services where NETWORK_NAME is not null and NAME not like '%XDB';
