在不带缓存组的ASP中，复制产生在TimesTen的表间；而在带缓存组的ASP中，复制产生在cache table之间。带缓冲组的复制仅支持只读和AWT缓存组。对只读缓存组，复制的意义在于保持状态的连续，而对AWT，复制可以保证数据不丢失。
假定active master为cachedb1，standby master为cachedb2
cachedb1>
CREATE DYNAMIC READONLY CACHE GROUP "RO"
AUTOREFRESH MODE INCREMENTAL INTERVAL 5 SECONDS
STATE PAUSED
FROM
"TTHR"."A" (
"ID" NUMBER(38) NOT NULL,
"NAME" VARCHAR2(32 BYTE),
PRIMARY KEY("ID")
)
cachedb1> cachegroups;
Cache Group TTHR.RO:
Cache Group Type: Read Only (Dynamic)
Autorefresh: Yes
Autorefresh Mode: Incremental
Autorefresh State: Paused <- 确保此状态是paused
Autorefresh Interval: 5 Seconds
Autorefresh Status: ok
Aging: LRU on
Root Table: TTHR.A
Table Type: Read Only缓存组的状态必须为paused，否则后续操作会报错，可使用alter cache group命令修改状态
5166: Autorefresh state ON for TTHR.RO is incompatible with replication store state Idle. Autorefresh state should be PAUSED. Alter the autorefresh state and reexecute statement.
cachedb1> alter cache group ro set autorefresh state paused;cachedb1> CREATE ACTIVE STANDBY PAIR cachedb1, cachedb2;cachedb1> call ttRepStateSet('ACTIVE');
cachedb1> call ttRepStateGet;
< ACTIVE, NO GRID >cachedb1> call ttrepstart;
cachedb1> select * from a;
cachedb1> select * from a where id = 1;
< 1, beijing >cachedb1>create user repadmin identified by timesten;
cachedb1> grant admin to repadmin;
$ ttRepAdmin -duplicate -from cachedb1 -host $(hostname) -uid repadmin -pwd timesten -keepCG cachedb2
Enter cache administrator UID: cacheadm
Enter cache administrator password: oracle
Waiting for the Duplicate operation to complete ...$ ttisql -v1 -e "set prompt 'cachedb2> '" "dsn=cachedb2;uid=tthr;pwd=timesten;oraclepwd=oracle"
cachedb2> call ttCacheStart;
cachedb2> call ttRepStateGet;
< IDLE, NO GRID >
cachedb2> call ttRepStart;
cachedb2> call ttRepStateGet;
< STANDBY, NO GRID >cachedb2> select * from a;
< 1, beijing >
cachedb2> select * from a where id = 2; <-只读
8151: TTHR.RO's replication role disallows the requested operation
cachedb1> select * from a where id = 2;
< 2, shanghai >
cachedb2> select * from a;
< 1, beijing >
< 2, shanghai > <- 可以看到cache group的数据已复制过来
目前1切正常建立AWT缓存组, 这时候active是cachedb2, standby是cachedb1, 全部进程以下：
cachedb2>
CREATE DYNAMIC ASYNCHRONOUS WRITETHROUGH CACHE GROUP "AWT"
FROM
"TTHR"."A" (
"ID" NUMBER(38) NOT NULL,
"NAME" VARCHAR2(32 BYTE),
PRIMARY KEY("ID")
)
AGING LRU ON
cachedb2> cachegroups;
Cache Group TTHR.AWT:
Cache Group Type: Asynchronous Writethrough (Dynamic)
Autorefresh: No
Aging: LRU on
Root Table: TTHR.A
Table Type: Propagate
cachedb2> call ttcachestart;
cachedb2> CREATE ACTIVE STANDBY PAIR cachedb2, cachedb1;
cachedb2> call ttrepstart;
cachedb2> call ttrepstateset('active');
cachedb2> call ttrepstateget;
< ACTIVE, NO GRID >
cachedb2> insert into a values(1, 'beijing');
cachedb2> commit;
cachedb2> select * from a;
< 1, beijing >
$ ttRepAdmin -duplicate -from cachedb2 -host $(hostname) -uid repadmin -pwd timesten -keepCG cachedb1
Enter cache administrator UID: cacheadm
Enter cache administrator password:
Waiting for the Duplicate operation to complete ...
$ ttisql -v1 -e "set prompt 'cachedb1> '" "dsn=cachedb1;uid=tthr;pwd=timesten;oraclepwd=oracle"
cachedb1> call ttrepstart;
cachedb1> call ttcachestart;
cachedb1> call ttrepstateget;
< STANDBY, NO GRID >
cachedb1> select * from a;
< 1, beijing >
cachedb1> insert into a values(2, 'shanghai');
16265: This store is currently the STANDBY. Change to TTHR.A not permitted.
cachedb2> insert into a values(2, 'shanghai');
cachedb1> select * from a;
< 1, beijing >
< 2, shanghai > <- 复制的数据
cachedb1> call ttrepstop;
cachedb1> call ttRepStateSet('ACTIVE');
cachedb1> call ttrepstateget;
< ACTIVE, NO GRID >
cachedb1> call ttRepStateSave('FAILED', 'cachedb2','timesten-hol');
$ ttdestroy cachedb2
$ ttRepAdmin -duplicate -from cachedb1 -host $(hostname) -uid repadmin -pwd timesten -keepCG -recoveringNode cachedb2
$ ttisql -v1 -e "set prompt 'cachedb2> '" "dsn=cachedb2;uid=tthr;pwd=timesten;oraclepwd=oracle"
cachedb2> call ttrepstart;
cachedb2> call ttcachestart;
calcachedb2> call ttrepstateget;
< STANDBY, NO GRID >
cachedb2> select * from a;
< 1, beijing >
< 2, shanghai >
cachedb2> insert into a values(3, 'guangzhou');
16265: This store is currently the STANDBY. Change to TTHR.A not permitted.
cachedb1> insert into a values(3, 'guangzhou');
cachedb2> select * from a;
< 1, beijing >
< 2, shanghai >
< 3, guangzhou >停止复制代理来摹拟active失效，以下是缓存组为read-only的情形，如果是AWT，也是类似的
cachedb1> call ttrepstop;将standby提升为active, 并标记之前的active为失效状态
cachedb2> call ttRepStateSet('ACTIVE');
cachedb2> call ttRepStateSave('FAILED', 'cachedb1','timesten-hol');这时候新的active可以LOAD数据了
cachedb2> select * from a;
< 1, beijing >
< 2, shanghai >
cachedb2> select * from a where id = 3;
< 3, guangzhou >烧毁原来的active，正常的情况下直接用ttdestroy便可
cachedb1> call ttcachestop;
cachedb1> drop active standby pair;
cachedb1> drop cache group ro;
cachedb1> exit
$ ttdestroy cachedb1重新的active克隆出standby，注意-keepCG -recoveringNode选项
$ ttRepAdmin -duplicate -from cachedb2 -host $(hostname) -uid repadmin -pwd timesten -keepCG -recoveringNode cachedb1
Enter cache administrator UID: cacheadm
Enter cache administrator password:
Waiting for the Duplicate operation to complete ...启动standby的复制和缓存代理
$ ttisql -v1 -e "set prompt 'cachedb1> '" "dsn=cachedb1;uid=tthr;pwd=timesten;oraclepwd=oracle"
cachedb1> call ttrepstart;
cachedb1> call ttcachestart;
cachedb1> call ttrepstateget;
< STANDBY, NO GRID >数据已复制到standby，但standby的缓存组不能进行LOAD操作
cachedb1> select * from a;
< 1, beijing >
< 2, shanghai >
< 3, guangzhou >
cachedb1> unload cache group ro;
16265: This store is currently the STANDBY. Change to TTHR.A not permitted.这类情况比较简单，由于复制时，数据是先到standby然后在active上提交的。因此很多操作都是自动的。
大不了，从standby升级为active后，再克隆出新的standby便可
如果复制是return twosafe, 以下是缓存组为read-only的情形
CREATE ACTIVE STANDBY PAIR cachedb1, cachedb2 return twosafe
cachedb2> unload cache group ro;
8099: TWOSAFE operation not permitted with AutoCommit = 1.
cachedb2> set autocommit 0;
cachedb2> unload cache group ro;
cachedb2> commit;
cachedb2> select * from a;
cachedb2> select * from a where id = 1;
< 1, beijing >
cachedb1> call ttrepstateget;
< STANDBY, NO GRID >
cachedb1> select * from a;
< 1, beijing >
cachedb1> call ttrepstop;
cachedb2> select * from a where id = 2; <- HANG了1会，结果还是出来了，
< 2, shanghai >
cachedb1> select * from a;
< 1, beijing > <- 不过数据自然是不会复制过去的了如果缓存组为AWT，并且传输模式为return twosafe，这时候会禁止active真个事务提交，这时候需要设置主端：
call ttRepSyncSet( null, null, 2);
commit;
ttRepStateSave('FAILED','standby_database','host_name')
然后再克隆standby假定active为cachedb1，standby为cachedb2
首先停止利用更新数据库。
cachedb1> call ttRepSubscriberWait(NULL, NULL, 'cachedb2', 'timesten-hol', 10);
< 00 > <- 返回值必须为00
call ttRepDeactivate();
cachedb1> call ttrepstop;
cachedb1> call ttRepDeactivate();
cachedb1> call ttrepstateget;
< IDLE, NO GRID >
cachedb2> call ttRepStateSet('ACTIVE');
cachedb2> call ttrepstateget;
< ACTIVE, NO GRID >
cachedb1> call ttrepstart;
cachedb1> call ttrepstateget;
< IDLE, NO GRID >
过1小会
cachedb1> call ttrepstateget;
< STANDBY, NO GRID >
好了，角色换过了了这个比较简单，如果DDLReplicationLevel 是2，则口令的修改会自动复制到standby。否则就必须手工在每个库中修改。例如：
cachedb2> alter user tthr identified by oracle;
User altered.
[oracle@timesten-hol ~]$ ttisql -v1 -e "set prompt 'cachedb1> '" "dsn=cachedb1;uid=tthr;pwd=timesten;oraclepwd=oracle"
7001: User authentication failed
[oracle@timesten-hol ~]$ ttisql -v1 -e "set prompt 'cachedb1> '" "dsn=cachedb1;uid=tthr;pwd=oracle;oraclepwd=oracle"
这个实际上是不常见的。
cache admin用户名在Oracle和TimesTen中必须是1样的，但口令可以不1样
所以改口令没甚么特别的，alter user便可。例如
Command> ALTER USER cacheadmin IDENTIFIED BY newpwd;
Command> passthrough 3;
Command> ALTER USER cacheadm IDENTIFIED BY newpwd;如果改用户名，就比较麻烦了，必须先删除掉所有的缓存组，因此不建议。
目前为止，谈的都是数据中心内部的HA场景，我们也能够建立1个位于灾备真个subscriber ，在故障时使其成可以继续与Oracle同步数据，第2个Oracle数据库也位于灾备端。
大致进程以下，由于需要建立第2个Oracle数据库，这里就不演示了。
http://www.oracledistilled.com/linux/configuring-an-oracle-timesten-logical-server-name-on-unix-based-systems/