Alter system checkpoint；
Alter system switch logfile；
Shutdown immediate；

sys@sfc12db> shutdown immediate;
ORA-00448: normal completion of background process
Alert.log
Job queue slave processes stopped
Tue Aug  9 17:58:05 2011
Error 1017 received logging on to the standby
------------------------------------------------------------
Check that the primary and standby are using a password file
and remote_login_passwordfile is set to SHARED or EXCLUSIVE,
and that the SYS password is same in the password files.
returning error ORA-16191
------------------------------------------------------------
Tue Aug  9 17:58:05 2011
Errors in file /apps/oracle/admin/sfc12db/bdump/sfc12db3_arc9_28977.trc:
ORA-16191: Primary log shipping client not logged on standby
PING[ARC9]: Heartbeat failed to connect to standby 'sfc12stb'. Error is 16191.
alter database recover managed standby database using current logfile
Tue Aug  9 23:30:52 2011
Media Recovery Start: Managed Standby Recovery (sfc12db1)
Tue Aug  9 23:30:52 2011
Managed Standby Recovery starting Real Time Apply
Tue Aug  9 23:30:53 2011
parallel recovery started with 3 processes
Media Recovery Log +STANDBY_ARCH/sfc12stb/archivelog/2011_08_09/thread_3_seq_75093.748.758760043
Media Recovery Log +STANDBY_ARCH/sfc12stb/archivelog/2011_08_09/thread_1_seq_74711.1087.758758331
Media Recovery Waiting for thread 2 sequence 46805
Fetching gap sequence in thread 2, gap sequence 46805-46904
Tue Aug  9 23:31:08 2011
Using STANDBY_ARCHIVE_DEST parameter default value as +STANDBY_ARCH
Redo Shipping Client Connected as PUBLIC
-- Connected User is Valid
RFS[1]: Assigned to RFS process 5332
RFS[1]: Identified database type as 'physical standby'
Tue Aug  9 23:31:08 2011
RFS LogMiner: Client disabled from further notification
Tue Aug  9 23:31:15 2011
FAL[client]: Failed to request gap sequence
GAP - thread 2 sequence 46805-46904
DBID 1192333070 branch 679867280
FAL[client]: All defined FAL servers have been attempted.

orapwd file=orapwsfc12db1 password=oracleracdb entries=10 force=y
orapwd file=orapwsfc12db2 password=oracleracdb entries=10 force=y
orapwd file=orapwsfc12db3 password=oracleracdb entries=10 force=y

orapwd file=orapwsfc12db1 password=oracleracdb entries=10 force=y
orapwd file=orapwsfc12db2 password=oracleracdb entries=10 force=y

alter database recover managed standby database cancel;
shutdown immediate
startup mount
alter database recover managed standby database using current logfile disconnect;

orapwd file=orapwsfc12db1 password=sfcs12pass entries=10 force=y
orapwd file=orapwsfc12db2 password=sfcs12pass entries=10 force=y
orapwd file=orapwsfc12db3 password=sfcs12pass entries=10 force=y

orapwd file=orapwsfc12db1 password=sfcs12pass entries=10 force=y
orapwd file=orapwsfc12db2 password=sfcs12pass entries=10 force=y

alter database recover managed standby database cancel;
shutdown immediate
startup mount
alter database recover managed standby database using current logfile disconnect;

Error Id: ORA-16191

Title: Primary log shipping client not logged on standby

Description:

Primary log shipping client not logged on standby

Action:

Check that primary and standby are using password files and that both primary and standby have the same SYS password. Restart primary and/or standby after ensuring that password file is accessible and REMOTE_LOGIN_PASSWORDFILE initialization parameter is set to SHARED or EXCLUSIVE.

Cause:

An attempt to ship redo to standby without logging on to standby or with invalid user credentials.

Error Id: ORA-00448

Title: normal completion of background process

Description:

normal completion of background process

Action:

Warm start the system.

Cause:

One of the background processes completed normally (i.e. exited). The background process thinks that somebody asked it to exit.

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