Online Redo logs instead of Standby Redo logs

RDBMS Version: 11.2.0.3/Platform : RHEL 6.3
To migrate a 3TB Database to a new DB server , we are going to use RMAN DUPLICATE.
Step1. Take full backup of DB + Standby Control file at primary site and transfer the Bkp files to Standby site
Step2. At standy site, we will run the RMAN duplicate target database for standby
After the above step, we don't want to create the standby redo logs because the newly restored DB in standby server is going to be the new Prod DB which application will be pointing to.
So, Can I skip the Standby Redo log creation part and create Online redo logs instead ?
As mentioned earlier, Our objective is not to create a proper Dataguard Standby DB setup. We just want to clone our DB to another server using RMAN Duplicate.

Tom wrote:
RDBMS Version: 11.2.0.3/Platform : RHEL 6.3
To migrate a 3TB Database to a new DB server , we are going to use RMAN DUPLICATE.
Step1. Take full backup of DB + Standby Control file at primary site and transfer the Bkp files to Standby site
Step2. At standy site, we will run the RMAN duplicate target database for standby
After the above step, we don't want to create the standby redo logs because the newly restored DB in standby server is going to be the new Prod DB which application will be pointing to.
So, Can I skip the Standby Redo log creation part and create Online redo logs instead ?
As mentioned earlier, Our objective is not to create a proper Dataguard Standby DB setup. We just want to clone our DB to another server using RMAN Duplicate.
Hi,
Take full backup of DB + Standby Control
We just want to clone our DB to another server using RMAN Duplicate
If you want only clone database of production, why you are take Standby controlfile?
If you don't want create standby database then, why you using DUPLICATE command with FOR STANDBY option.
You can use DUPLICATE command for clone database, without for standby option.
If you say no, we want create standby database and we will perform swithover,
then yes, you can use online redo logs for max performance mode.
and you can create standby redo logs on all database, but this redo logs will use by database when database role
is standby.
Regards
Mahir M. Quluzade

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Standby Redo log creation

DB version: 11.2
OS : AIX 6.1
We have a 2 node RAC. We have one Disk group for all datafiles, tempfiles, redo logs,..etc.
Currenly in our primary DB, Redo logs look like
SQL> SELECT a.group#, b.thread#, a.member, b.bytes
FROM v$logfile a, v$log b WHERE a.group# = b.group#
order by a.group# , b.thread# 2    3 ;
         GROUP#         THREAD# MEMBER                                BYTES
              1               1 +ORCL_DG/orcl/orcl_log01.dbf         104857600
              2               1 +ORCL_DG/orcl/orcl_log02.dbf         104857600
              3               1 +ORCL_DG/orcl/orcl_log03.dbf         104857600
              4               2 +ORCL_DG/orcl/orcl_log04.dbf         104857600
              5               2 +ORCL_DG/orcl/orcl_log05.dbf         104857600
              6               2 +ORCL_DG/orcl/orcl_log06.dbf         104857600
6 rows selected.
1 member per group
3 group per instanceWe need to create a physical standby DB for the above DB with Real Time apply. For standby Redo logs, I need one extra log file for each Instance.
So, I am going to add
     group# 7 for thread 1
     and
     group# 8 for thread 2
Finally , SRLs will look like
         GROUP#         THREAD# MEMBER                                BYTES
              1               1 +ORCL_DG/orcl/orcl_log01.dbf         104857600
              2               1 +ORCL_DG/orcl/orcl_log02.dbf         104857600
              3               1 +ORCL_DG/orcl/orcl_log03.dbf         104857600
           7               1 +ORCL_DG/orcl/orcl_log07.dbf         104857600 -------> Additional
              4               2 +ORCL_DG/orcl/orcl_log04.dbf         104857600
              5               2 +ORCL_DG/orcl/orcl_log05.dbf         104857600
              6               2 +ORCL_DG/orcl/orcl_log06.dbf         104857600
           8               2 +ORCL_DG/orcl/orcl_log08.dbf         104857600 -------> AdditionalAnything wrong with my proposed SRL creation ?

JOE_humble wrote:
DB version: 11.2
OS : AIX 6.1
We have a 2 node RAC. We have one Disk group for all datafiles, tempfiles, redo logs,..etc.
Currenly in our primary DB, Redo logs look like
SQL> SELECT a.group#, b.thread#, a.member, b.bytes
FROM v$logfile a, v$log b WHERE a.group# = b.group#
order by a.group# , b.thread# 2    3 ;
GROUP#         THREAD# MEMBER                                BYTES
1               1 +ORCL_DG/orcl/orcl_log01.dbf         104857600
2               1 +ORCL_DG/orcl/orcl_log02.dbf         104857600
3               1 +ORCL_DG/orcl/orcl_log03.dbf         104857600
4               2 +ORCL_DG/orcl/orcl_log04.dbf         104857600
5               2 +ORCL_DG/orcl/orcl_log05.dbf         104857600
6               2 +ORCL_DG/orcl/orcl_log06.dbf         104857600
6 rows selected.
1 member per group
3 group per instanceWe need to create a physical standby DB for the above DB with Real Time apply. For standby Redo logs, I need one extra log file for each Instance.
So, I am going to add
     group# 7 for thread 1
     and
     group# 8 for thread 2
Finally , SRLs will look like
GROUP#         THREAD# MEMBER                                BYTES
1               1 +ORCL_DG/orcl/orcl_log01.dbf         104857600
2               1 +ORCL_DG/orcl/orcl_log02.dbf         104857600
3               1 +ORCL_DG/orcl/orcl_log03.dbf         104857600
           7               1 +ORCL_DG/orcl/orcl_log07.dbf         104857600 -------> Additional
4               2 +ORCL_DG/orcl/orcl_log04.dbf         104857600
5               2 +ORCL_DG/orcl/orcl_log05.dbf         104857600
6               2 +ORCL_DG/orcl/orcl_log06.dbf         104857600
           8               2 +ORCL_DG/orcl/orcl_log08.dbf         104857600 -------> AdditionalAnything wrong with my proposed SRL creation ?You have to create equal numbers & equal or greater size of standby redo log files than Online redo log files.
Refer http://www.pythian.com/news/581/oracle-standby-redo-logs/ to configure standby redo log files.

Standby redo log does not exist...

Hello,
Oracle 11.2.0.2, running on Solaris
This is kind of a continuation of a previous thread, but this is a different question:
I have a DG configuration, with the primary database having 2 redo logs per redo log group.
And, it has 2 redo logs for the standby redo log groups.
But I just found out something very strange:
For the standby redo log group, even though the database shows it has two redo log files per group, the second file does not actually exist on the file system.
And, I have no idea where it is, or why the database is not complaining about it.
See below:
SQL> select * from v$logfile;
         GROUP# STATUS    TYPE    MEMBER                                        IS_
             11           STANDBY /opt/oracle/oradata2/PROD/REDO01A_STDBY.log NO
             11           STANDBY /opt/oracle/oradata3/PROD/REDO01B_STDBY.log NO    <== does not exist on file system
             12           STANDBY /opt/oracle/oradata2/PROD/REDO02A_STDBY.log NO
             12           STANDBY /opt/oracle/oradata3/PROD/REDO02B_STDBY.log NO    <== does not exist on file system
             13           STANDBY /opt/oracle/oradata2/PROD/REDO03A_STDBY.log NO
             13           STANDBY /opt/oracle/oradata3/PROD/REDO03B_STDBY.log NO    <== does not exist on file system
             14           STANDBY /opt/oracle/oradata2/PROD/REDO04A_STDBY.log NO
             14           STANDBY /opt/oracle/oradata3/PROD/REDO04B_STDBY.log NO    <== does not exist on file system
             15           STANDBY /opt/oracle/oradata2/PROD/REDO05A_STDBY.log NO
             15           STANDBY /opt/oracle/oradata3/PROD/REDO05B_STDBY.log NO    <== does not exist on file system
              5           ONLINE /opt/oracle/oradata1/PROD/REDO05A.log       NO
              5           ONLINE /opt/oracle/oradata2/PROD/REDO05B.log       NO
              6           ONLINE /opt/oracle/oradata1/PROD/REDO06A.log       NO
              6           ONLINE /opt/oracle/oradata2/PROD/REDO06B.log       NO
              7           ONLINE /opt/oracle/oradata1/PROD/REDO07A.log       NO
              7           ONLINE /opt/oracle/oradata2/PROD/REDO07B.log       NO
              8           ONLINE /opt/oracle/oradata1/PROD/REDO08A.log       NO
              8           ONLINE /opt/oracle/oradata2/PROD/REDO08B.log       NO
18 rows selected.
Notice below that the "B" redo logs do not exist.
SQL> !ls -l /opt/oracle/oradata3/PROD/REDO01B_STDBY.log
/opt/oracle/oradata3/PROD/REDO01B_STDBY.log: No such file or directory
SQL> !ls -l /opt/oracle/oradata3/PROD/REDO02B_STDBY.log
/opt/oracle/oradata3/PROD/REDO02B_STDBY.log: No such file or directory
SQL> !ls -l /opt/oracle/oradata3/PROD/REDO03B_STDBY.log
/opt/oracle/oradata3/PROD/REDO03B_STDBY.log: No such file or directory
SQL> !ls -l /opt/oracle/oradata3/PROD/REDO04B_STDBY.log
/opt/oracle/oradata3/PROD/REDO04B_STDBY.log: No such file or directory
SQL> !ls -l /opt/oracle/oradata3/PROD/REDO05B_STDBY.log
/opt/oracle/oradata3/PROD/REDO05B_STDBY.log: No such file or directory
But here, you can see that the "A" redo logs actually do exist.
SQL> !ls -l /opt/oracle/oradata2/PROD/REDO01A_STDBY.log
-rw-r-----   1 oracle   dba      536871424 Jan 7 2011 /opt/oracle/oradata2/PROD/REDO01A_STDBY.log

Hello;
I'm able to recreate
SQL> select * from v$logfile;
    GROUP# STATUS TYPE    MEMBER                                             IS_
         3         ONLINE /u01/app/oracle/flash_recovery_area/RECOVER2/onlin YES
                           elog/o1_mf_3_8gtxxrl6_.log
         2         ONLINE /u01/app/oracle/flash_recovery_area/RECOVER2/onlin YES
                           elog/o1_mf_2_8gtxxr4f_.log
         1         ONLINE /u01/app/oracle/flash_recovery_area/RECOVER2/onlin YES
                           elog/o1_mf_1_8gtxxqng_.log
         4         STANDBY /u01/app/oracle/oradata/RECOVER2/redo04.log        NO
         5         STANDBY /u01/app/oracle/oradata/RECOVER2/redo05.log        NO
         6         STANDBY /u01/app/oracle/oradata/RECOVER2/redo06.log        NOAnd then
SQL> !ls -al /u01/app/oracle/oradata/RECOVER2/redo04.log
ls: /u01/app/oracle/oradata/RECOVER2/redo04.log: No such file or directoryChecking... *Not there, but Oracle ( 11.2.0.3 ) allows clean up without barking. Had only one member so I did GROUP drop.
SQL> ALTER DATABASE DROP LOGFILE GROUP 4;
Database altered.
SQL> select * from v$logfile;
    GROUP# STATUS TYPE    MEMBER                                             IS_
         3         ONLINE /u01/app/oracle/flash_recovery_area/RECOVER2/onlin YES
                           elog/o1_mf_3_8gtxxrl6_.log
         2         ONLINE /u01/app/oracle/flash_recovery_area/RECOVER2/onlin YES
                           elog/o1_mf_2_8gtxxr4f_.log
         1         ONLINE /u01/app/oracle/flash_recovery_area/RECOVER2/onlin YES
                           elog/o1_mf_1_8gtxxqng_.log
         5         STANDBY /u01/app/oracle/oradata/RECOVER2/redo05.log        NO
         6         STANDBY /u01/app/oracle/oradata/RECOVER2/redo06.log        NO
SQL> Best Regards
mseberg

What is the purpose of standby redo log files

Hi,
What is the purpose of the standby redo log files in DR?
what if the standby redo log files are created? or else not created?
Please explain
Thanks

3.1.3 Configure a Standby Redo LogA standby redo log is required for the maximum protection and maximum availability modes and the LGWR ASYNC transport mode is recommended for all databases. Data Guard can recover and apply more redo data from a standby redo log than from archived redo log files alone.
You should plan the standby redo log configuration and create all required log groups and group members when you create the standby database. For increased availability, consider multiplexing the standby redo log files, similar to the way that online redo log files are multiplexed.>
Reference http://download.oracle.com/docs/cd/B19306_01/server.102/b14239/create_ps.htm#i1225703
HTH
Anand

Dataguard lost both Primary redo log and standby redo log files

Hi,
I am new to data guard, i came acorss a scenario where we loose both primary redo log file and standby redo log files.
Can someone please help me understand how to recover from this situation.
Thanks!

>loose both primary redo log file and standby redo log files
We have to be very clear.
There are (set A) online redo log files and (set B) standby redo log files at (location 1) Primary and (location 2) Standby.
The standby redo log files, depending on the configuration, aren't strictly mandatory. The standby can be applying redo without online redo log files present as well, depending on how it was setup.
So, the question is : Did you lose online redo log files at the primary ? Didn't the primary shutdown itself then ? If so, you have to do an incomplete recovery at the primary OR switch over to the standby (which may or may not have received the last transaction, depending on how it was configured and operating) OR restore from the standby (again, with possible loss of transactions) to the primary.
Hemant K Chitale

Use of standby redo log files in primary database

Hi All,
What is the exact use of setting up standby redo log files in the primary database on a data guard setup?
any good documents?

A standby redo log is required for the maximum protection and maximum availability modes and the LGWR ASYNC transport mode is recommended for all databases. Data Guard can recover and apply more redo data from a standby redo log than from archived redo log files alone.
You should plan the standby redo log configuration and create all required log groups and group members when you create the standby database. For increased availability, consider multiplexing the standby redo log files, similar to the way that online redo log files are multiplexed.
refer the link,and Perform the following steps to configure the standby redo log.:-
http://download.oracle.com/docs/cd/B19306_01/server.102/b14239/create_ps.htm#i1225703
If the real-time apply feature is enabled, log apply services can apply redo data as it is received, without waiting for the current standby redo log file to be archived. This results in faster switchover and failover times because the standby redo log files have been applied already to the standby database by the time the failover or switchover begins.
refer the link
http://download.oracle.com/docs/cd/B19306_01/server.102/b14239/log_apply.htm#i1023371

When is anything written to standby redo logs on standby database?

I am on Oracle 10.2.0.4 on HP UNIX. I have read Oracle 10.2 concepts guide on technet.oracle.com, have read may article on metalink and internet, yet I am unable to verify when anything is written to standby redo logs on stand by database.
I have a simple database reconfiguration: a primary database and one standby database.
I created primary database and set up log_archive_dest_2 to use LGWR SYNC AFFIRM
I have created standby redo logs on primary.
alter database add standby logfile GROUP
I create standby control file on primary.
I copied all the primary information to create standby database. I have put standby database in managed recovery.
I did archive log switches, I created a table and inserted information in table.
I never saw standby redo logs updated on standby database by looking at timestamp of standby redo log files.
I then setup database in maximum availability mode by running following on primary:
Alter database set standby database to maximize availability
When I do insert into my tables, I do see standby redo log files on primary database being updated, but I have never seen standby redo logs on standby database updated. Why?
I am still at loss when actually standby redo logs are updated on standby database.
When I read Oracle 9i database documentation on data guard, it says that you do not need standby redo logs on primary instead you need them on standby. Only reason, you need them on primary is from primary changes role to standby database, so standby redo logs on standby database should be updated instead of standby redo logs on primary.

What is the PROTECTION_MODE ,PROTECTION_LEVEL values of your database.
As per metalink:--
Create standby redo log files, if necessary:
Standby redo logs are necessary for the higher protection levels such as
Guaranteed, Instant, and Rapid. In these protection modes LGWR from the
Primary host writes transactions directly to the standby redo logs.
This enables no data loss solutions and reduces the amount of data loss
in the event of failure. Standby redo logs are not necessary if you are using
the delayed protection mode.
If you configure standby redo on the standby then you should also configure
standby redo logs on the primary database. Even though the standby redo logs
are not used when the database is running in the primary role, configuring
the standby redo logs on the primary database is recommended in preparation
for an eventual switchover operation.
Standby redo logs must be archived before the data can be applied to the
standby database. The standby archival operation occurs automatically, even if
the standby database is not in ARCHIVELOG mode. However, the archiver process
must be started on the standby database. Note that the use of the archiver
process (ARCn) is a requirement for selection of a standby redo log.
METALINK ID:- Doc ID: Note:219344.1
Edited by: Anand... on Sep 15, 2008 2:15 AM

Dataguard Solution for standby redo log file groups

Respected Experts,
My database version is 10.2.0.1.0 and Red Hat 5 os.I want to create a standby database using RMAN.
Can any one help me with the full steps.And i'm also confuse about number of standby redo log file members
need to be created.
Thanks and Regards
Monoj Das

My database version is 10.2.0.1.0 and Red Hat 5 os.I want to create a standby database using RMAN.To configure standby either you can use duplicate target database for standby
or
1) restore standby controlfile
2) mount standby database
3) restore database
and configure standby paraemter then start MRP, will do.
http://docs.oracle.com/cd/B19306_01/server.102/b14239/create_ps.htm
Can any one help me with the full steps.And i'm also confuse about number of standby redo log file members
need to be created.It depends which parameter you want to use, if you mention log_archive_dest_2='service ARCH ' then no need to create any standby redo log file groups,
If you use log_archive_dest_2='service LGWR ' here transport will be in terms of redo and you need standby redo log files on standby database. Which is realtime.
When you use LGWR, data lost will be less if in case of any online redo log file lost. which is recommended.
HTH.

Where RFS exactly write redo data ? ( archived redo log or standby redo log ) ?

Good Morning to all ;
I am getting bit confused from oracle official link . REF_LINK : Log Apply Services
Redo data transmitted from the primary database is received by the RFS on the standby system ,
where the RFS process writes the redo data to either archived redo log files or standby redo log files.
In standby site , does rfs write redo data in any one file or both ?
Thanks in advance ..

Hi GTS,
GTS (DBA) wrote:
Primary & standby log file size should be same - this is okay.
1) what are trying to disclose about largest & smallest here ? - You are confusing.
Read: http://docs.oracle.com/cd/E11882_01/server.112/e25608/log_transport.htm#SBYDB4752
"Each standby redo log file must be at least as large as the largest redo log file in the redo log of the redo source database. For administrative ease, Oracle recommends that all redo log files in the redo log at the redo source database and the standby redo log at a redo transport destination be of the same size."
GTS (DBA) wrote:
2) what abt group members ? should be same as primary or need to add some members additionally. ?
Data Guard best practice for performance, is to create one member per each group in standby DB. on standby DB, one member per group is reasonable enough. why? to avoid write penalty; writing to more than one log files at the standby DB.
SCENARIO 1: if in your source primary DB you have 2 log member per group, in standby DB you can have 1 member per group, additionally create an extra group.
primary
standby
Member per group
2
1
Number of log group
4
5
SCENARIO 2: you can also have this scenario 2 but i will not encourage it
primary
standby
Member per group
2
2
Number of log group
4
5
GTS (DBA) wrote:
All standby redo logs of the correct size have not yet been archived.
- at this situation , can we force on standby site ? any possibilities ?
you can not force it , just size your standby redo files correctly and make sure you don not have network failure that will cause redo gap.
hope there is clarity now
Tobi

Standby redo log file

Hi,
From oracle document i know in the standby side the RFS process writes to Standby redo log file -> archive log and the MRP procees applys the archive logs to the standby database.
my question is ,if we dont create standby redo log file what happens?

Hello;
When redo is received by an RFS on the standby , the RFS process writes the redo data into archived redo logs or optionally to the SRL.
Standby Redo Logs is where the RFS process at your Standby database writes incoming redo, they help performance because the RFS does not have to create the Archive log file.
Standby redo logs are a component of the Data Guard setup. They should be the same size as the redo logs on the Primary.
Standby Redo Logs do not not to be multiplexed.
I would create SRL them on both the Primary and the Standby. Think of it as one database in either Standby or Primary Mode. If you have to switchover you still need them.
If you have SRL's setup and need to do either a failover or switchover it should occur faster and safer.
Best Regards
mseberg

The file structure online redo log, archived redo log and standby redo log

I have read some Oracle documentation for file structure and settings in Data Guard environment. But I still have some doubts. What is the best file structure or settings in Oracle 10.2.0.4 on UNIX for a data guard environment with 4 primary databases and 4 physical standby databases. Based on Oracle documents, there are 3 redo logs. They are: online redo logs, archived redo logs and standby redo logs. The basic settings are:
1. Online redo logs --- This redo log must be on Primary database and logical standby database. But it is not necessary to be on physical standby database because physical standby is not open. It doesn't generate redo log. However, if don't set up online redo log on physical standby, when primary failover and switch standby as primary. How can standby perform without online redo logs? In my standby databases, online redo logs have been set up.
2. Archived redo logs --- It is obviously that primary database, logical and physical standby database all need to have this log file being set up. Primary use it to archive log files and ship to standby. Standby use it to receive data from archived log and apply to database.
3. Standby redo logs --- In the document, it says A standby redo log is similar to an online redo log, except that a standby redo log is used to store redo data received from another database. A standby redo log is required if you want to implement: The maximum protection and maximum availability levels of data protection and Real-time apply as well as Cascaded destinations. So it seems that this standby redo log only should be set up on standby database, not on primary database. Am my understanding correct? Because I review current redo log settings on my environment, I have found that Standby redo log directory and files have been set up on both primary and standby databases. I would like to get more information and education from experts. What is the best setting or structure on primary and standby database?

FZheng:
Thanks for your input. It is clear that we need 3 type of redo logs on both databases. You answer my question.
But I have another one. In oracle ducument, it says If you have configured a standby redo log on one or more standby databases in the configuration, ensure the size of the current standby redo log file on each standby database exactly matches the size of the current online redo log file on the primary database. It says: At log switch time, if there are no available standby redo log files that match the size of the new current online redo log file on the primary database. The primary database will shut down
My current one data gurard envirnment setting is: On primary DB, online redo log group size is 512M and standby redo log group size is 500M. On the standby DB, online redo log group size is 500M and standby redo log group size is 750M.
This was setup by someone I don't know. Is this setting OK? or I should change Standby Redo Log on standby DB to 512M to exactly meatch with redo log size on primary?
Edited by: 853153 on Jun 22, 2011 9:42 AM

Resizing online and standby redo log in dataguard setup.

In 10gr2 dataguard i would like to increase redo logsize from 50M to 100M.
on primary
standby_file_management=manual
added online redo groups with 100M
log switched
drop old one and readded with 100m
deleted log added in step2.
same for standby redo logs.
On standby
was able to resize standby redo logs.
but cannot resize online redologs status is clearing or clearing_current.
please comment. thanks.

I assume you just had to wait until the Primary switched out of that online log so it became inactive at the standby as well? We track where the Primary is by marking the online redo log files at the standby as clearing_current so you can tell where the primary was at any given moment.
Make sure you create new standby redo log files at the Primary and Standby to match the new online redo log file size.
Larry

Online redo logs vs standby redo logs

Hi All,
Oracle version : 10.2.0.4
OS : SunOS 5.10 Generic_118855-36 i86pc i386 i86pc
This might be a silly question for the experts :(
We are having 2 standby databases and 1 logical database. Everything is running fine , I have one confusion : My primary server having 3 online redo log files and 3 standby redo log files (on primary local), but as per the architecture standby redo logs should be on standby server.My question is whether standby redo logs on standby are online redo logs of standby server or standby redo logs of primary server. e.g If i perform a log switch on primary then what is the role of sync and affirm, will lgwr write parallel on online redo logs ,standby redo logs (of primary) or online redo logs (of primary) and online redo logs (which is known as standby redo logs on standby ). Please help me to understand the scenerio.
Thanks in advance!

RFS receives redo information from the primary database.
RFS can write the redo into standby redo logs or directly to archived redo logs. Each LNSn and ARCn process from the primary database has its own RFS process.
A standby redo log is used only when the database is in the standby role to store redo data received from the primary database. Standby redo logs form a separate pool of log file groups.
Configuring standby redo log files is highly recommended on all standby databases in a Data Guard configuration, including the primary database to aid in role reversal.
A standby redo log is required to implement:
• The maximum protection and maximum availability levels of data protection
• Real-time apply
• Cascaded redo log destinations
Standby redo logs are recommended for maximum performance data protection mode. Unless you are using the real-time apply feature, standby redo logs must be archived before the data can be applied to the standby database. The standby archival operation occurs automatically.

Delete standby redo log from primary database

Hi all,
I'm trying to drop standby logfiles on primary database (other database that I'm configuring the DG).
The members of the standby log groups don't exists on file system.
Somebody have deleted these files. Its old configuration where the files were in file system. Now they are in ASM.
When I try to drop the standby logfiles I got the following error:
SQL> alter database clear logfile group 7;
alter database clear logfile group 7
ERROR at line 1:
ORA-19528: redo logs being cleared may need access to files
SQL> select * from v$logfile order by 1;
    GROUP# STATUS TYPE    MEMBER                                                                           IS_
         1         ONLINE +REDO1/proj/onlinelog/group_1.256.340558657                                     NO
         1         ONLINE +REDO2/proj/onlinelog/group_1.256.340558659                                     NO
         2         ONLINE +REDO1/proj/onlinelog/group_2.257.340558879                                     NO
         2         ONLINE +REDO2/proj/onlinelog/group_2.259.340558879                                     NO
         3         ONLINE +REDO1/proj/onlinelog/group_3.258.340558707                                     NO
         3         ONLINE +REDO2/proj/onlinelog/group_3.257.340558709                                     NO
         4         ONLINE +REDO2/proj/onlinelog/group_4.258.340558713                                     NO
         4         ONLINE +REDO1/proj/onlinelog/group_4.259.340558711                                     NO
         5         ONLINE +REDO2/proj/onlinelog/group_5.260.340558965                                     NO
         5         ONLINE +REDO1/proj/onlinelog/group_5.260.340558963                                     NO
         6         ONLINE +REDO1/proj/onlinelog/group_6.261.340558967                                     NO
         6         ONLINE +REDO2/proj/onlinelog/group_6.261.340558967                                     NO
         7         STANDBY /oracle/proj/onlinelog2/redo_702.log                                            NO
         7         STANDBY /oracle/proj/onlinelog1/redo_701.log                                            NO
         8         STANDBY /oracle/proj/onlinelog2/redo_802.log                                            NO
         8         STANDBY /oracle/proj/onlinelog1/redo_801.log                                            NO
         9         STANDBY /oracle/proj/onlinelog2/redo_902.log                                            NO
         9         STANDBY /oracle/proj/onlinelog1/redo_901.log                                            NO
        10         STANDBY /oracle/proj/onlinelog1/redo_1001.log                                           NO
        10         STANDBY /oracle/proj/onlinelog2/redo_1002.log                                           NO
20 rows selected.
SQL> select * from v$standby_log order by 1;
    GROUP# DBID            THREAD# SEQUENCE#      BYTES       USED ARC STATUS     FIRST_CHANGE# FIRST_TIM LAST_CHANGE# LAST_TIME
         7 UNASSIGNED            0          0 104854601        512 YES UNASSIGNED             0                      0
         8 UNASSIGNED            0          0 104854601        512 YES UNASSIGNED             0                      0
         9 UNASSIGNED            0          0 104854601        512 YES UNASSIGNED             0                      0
        10 UNASSIGNED            0          0 104854601        512 YES UNASSIGNED             0                      0What can I do to drop these reference?
Any other solution instead of edit the controlfile and stop/start tghe database?
thank you!!!!

Hello;
Well Oracle thinks the files are there, but I remember a bug on metalink where the controlfile still had them, but they were not on the file system. Can you confirm they exist?
Meanwhile I check my notes for the Oracle doc nunber.
Bug 6128242: TRYING TO DROP STANDBY LOG FAILS WITH ORA-19528
So if you are Oracle 10 this might be the issue.
workaround is to re-create the controlfile without the incorrect logfile. ( Yuk!! )
ORA-01156 When Adding Or Dropping Redo Logs [ID 452152.1]
Best Regards
mseberg
Edited by: mseberg on Oct 31, 2011 5:09 PM

Online Redo logs instead of Standby Redo logs

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