Data Guard : Standby Redo Log CONFUSION
Trying to set up test Standby db on 10.2.0
I am well confused about below step 3.1.3, how is the normal redo linked with standby redo, should standby not be members of orginal redo groups?
http://download.oracle.com/docs/cd/B19306_01/server.102/b14239/create_ps.htm#i1225703
Original redo logs:
SQL> select * from v$log;
GROUP# THREAD# SEQUENCE# BYTES MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIME
1 1 28 52428800 1 YES INACTIVE 375136 22-NOV-07
2 1 29 52428800 1 YES INACTIVE 375138 22-NOV-07
3 1 30 52428800 1 NO CURRENT 375143 22-NOV-07I added below from notes:
ALTER DATABASE ADD STANDBY LOGFILE GROUP 10
('/u01/oracle/oradata/db01/redo01_stb.log') SIZE 50M;
ALTER DATABASE ADD STANDBY LOGFILE GROUP 11
('/u02/oracle/oradata/db01/redo02_stb.log') SIZE 50M;
ALTER DATABASE ADD STANDBY LOGFILE GROUP 12
('/u03/oracle/oradata/db01/redo03_stb.log') SIZE 50M;After few alter system switch logfile; I still have:
GROUP# THREAD# SEQUENCE# ARC STATUS
10 0 0 YES UNASSIGNED
11 0 0 YES UNASSIGNED
12 0 0 YES UNASSIGNEDAll are UNASSIGNED, should one standby group not be ACTIVE like the above link shows.
Many think for any help
First things first:
From the Docs.:
"Minimally, the configuration should have one more standby redo log file group than the number of online redo log file groups on the primary database. However, the recommended number of standby redo log file groups is dependent on the number of threads on the primary database. Use the following equation to determine an appropriate number of standby redo log file groups:
(maximum number of logfiles for each thread + 1) * maximum number of threads
Using this equation reduces the likelihood that the primary instance's log writer (LGWR) process will be blocked because a standby redo log file cannot be allocated on the standby database. For example, if the primary database has 2 log files for each thread and 2 threads, then 6 standby redo log file groups are needed on the standby database."
You are 1 short!
Similar Messages
-
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 -
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. -
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 -
Standby redo log group for particular thread
hi masters,
actually i am performing an experiment to create physical standbyt database on the same machine as my primary database.
i ma going according to 'data guard admin guide'. while section for ading standby redo log group,it says that you have to add standby redo log group to "thread"....
what is this thread? and how can i foind to which thread i have to assign the next redo log group??
how can i find current thread??
what if i dont add "to thread' clause in my statement:-
ALTER DATABASE ADD STANDBY LOGFILE THREAD 5
2> ('/oracle/dbs/log1c.rdo','/oracle/dbs/log2c.rdo') SIZE 500M;
thanks and regards
VDVikrant,
First a question: Do you have a RAC instance? If so the paragraph even doesn't apply to you and I'm not sure why you are questioning it.
Secondly
"The THREAD clause is required only if you want to add one or more standby redo log
file groups to a specific primary database thread. If you do not include the THREAD
clause and the configuration uses Real Application Clusters (RAC), Data Guard will
automatically assign standby redo log file groups to threads at runtime as they are
needed by the various RAC instances."
this means you dont have to specify thread for RAC,as it will allocate one according to current thread.
Your conclusion is incorrect.
Where do you read the word 'current'?
Oracle will likely simply make sure each instance has sufficient standby redolog groups, the requirement is 1 standby redolog group per group + 1 extra.
Sybrand Bakker
Senior Oracle DBA -
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 -
Standby Redo Log just sits as IN-MEMORY
Hi, I have shipped an archived redo log from my Primary to my physical standby.
I can see the log arriving at my Standby and being applied
select thread#, max(sequence#) "Last Standby Seq Received"
from v$archived_log val, v$database vdb
where val.resetlogs_change# = vdb.resetlogs_change#
group by thread# order by 1;
returns
THREAD# Last Standby Seq Received
1 151
select thread#, max(sequence#) "Last Standby Seq Applied"
from v$archived_log val, v$database vdb
where val.resetlogs_change# = vdb.resetlogs_change#
and applied='YES'
group by thread# order by 1;
THREAD# Last Standby Seq Applied
1 150
select stamp,name,applied
from v$archived_log
where applied != 'YES'
STAMP
NAME
APPLIED
827498375
/home/app/oracle/fast_recovery_area/STANDBYL/archivelog/2013_09_30/o1_mf_1_151_9
4lrqpj3_.arc
IN-MEMORY
This log continually sits like this
I know that Redo Appply is active
select * from v$managed_standby where process = 'MRP0';
PROCESS PID STATUS CLIENT_P
CLIENT_PID
CLIENT_DBID
GROUP# RESETLOG_ID THREAD# SEQUENCE#
BLOCK# BLOCKS DELAY_MINS KNOWN_AGENTS ACTIVE_AGENTS
MRP0 3068 APPLYING_LOG N/A
N/A
N/A
N/A 820252586 1 152
5038 102400 0 3 3
It looks as if 151 has been applied - yet
select thread#, max(sequence#) "Last Standby Seq Applied"
from v$archived_log val, v$database vdb
where val.resetlogs_change# = vdb.resetlogs_change#
and applied='YES'
group by thread# order by 1;
still shows 150 !
151 is not that big, I still would have expected it to have applied by now ( in excess of 30 mins )
Also I know there is no defer or time delay on the archive_destination setting on the Primary.
Any ideas why this standby redo log just sits IN-MEMORY ?
thanks,
JimHello;
Not able to reproduce issue. Using Oracle 11.2.0.3 without Real-time apply.
select thread#, max(sequence#) "Last Standby Seq Received"
from v$archived_log val, v$database vdb
where val.resetlogs_change# = vdb.resetlogs_change#
group by thread# order by 1;
THREAD# Last Standby Seq Received
1 194
select thread#, max(sequence#) "Last Standby Seq Applied"
from v$archived_log val, v$database vdb
where val.resetlogs_change# = vdb.resetlogs_change#
and applied='YES'
group by thread# order by 1;
THREAD# Last Standby Seq Applied
1 194
select thread#, max(sequence#) "Last Standby Seq Applied"
from v$archived_log val, v$database vdb
where val.resetlogs_change# = vdb.resetlogs_change#
And Applied='YES'
group by thread# order by 1;
THREAD# Last Standby Seq Applied
1 194
SELECT ARCH.THREAD# "Thread", ARCH.SEQUENCE# "Last Sequence Received", APPL.SEQUENCE# "Last Sequence Applied"
FROM
(SELECT THREAD# ,SEQUENCE# FROM V$ARCHIVED_LOG WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME) FROM V$ARCHIVED_LOG GROUP BY THREAD#)) ARCH,
(SELECT THREAD# ,SEQUENCE# FROM V$LOG_HISTORY WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME) FROM V$LOG_HISTORY GROUP BY THREAD#)) APPL
WHERE
Arch.Thread# = Appl.Thread#
ORDER BY 1;
Thread Last Sequence Received Last Sequence Applied
1 194 194
select * from v$managed_standby where process = 'MRP0';
( shows the next sequence 195 on mine )
Is it possible the Standby has one extra archive? I've noticed that sometime you will see one extra on that side which appears to have nothing to do with the Data Guard process.
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
Thanks3.1.3 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 DasMy 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. -
RMAN,Data Guard and Archive log deletion
Our DG environment is running Oracle 11g R2
we have a 3 node DG environment with
A being the Primary
B and C being Active Data Guard Standbys
Backups are taken off of B and go directly to tape.
Standby Redo Logs and Fast Recovery Area are being used
Taking recommendation from "Using Recovery Manager with Oracle Data Guard in Oracle Database 10g"
RMAN Setting on Primary ("A")
CONFIGURE ARCHIVELOG DELETION POLICY TO APPLIED ON STANDBY
RMAN Setting on Standby ("B") where Backup is done
CONFIGURE ARCHIVELOG DELETION POLICY TO NONE
RMAN Setting on other Standby ("C")
CONFIGURE ARCHIVELOG DELETION POLICY TO APPLIED ON STANDBY
How can we know what archive logs are eligible to be deleted from "A" and "C" ?
When does the delete take place?
How can we tell when the archive logs are being deleted from "A" and "C" ?Dear user10260925,
The documentation that you have read is reliable but insufficient.
The Oracle can manage the archivelog directory and knows which one is eligible for the deletion. Those stuff you have posted in here has been taken from the online documentation and is supported and can be used when the Oracle knows and manages the archivelogs. That is simply called the flash recovery area. Please read about the FRA in this very moment.
Under normal circumstances people in the industry uses some scripts to achive the archivelog deletion on the standby system.
Here is a useful example to you;
# Remove old archivelogs
00,30 * * * * /home/oracle/scripts/delete_applied_redo_logs_OPTSTBY.sh
vals3:/home/oracle#cat /home/oracle/scripts/delete_applied_redo_logs_OPTSTBY.sh
export ORACLE_SID=optstby
export ORACLE_HOME=/oracle/product/10.2.0/db_1
cd /db/optima/archive/OPTPROD/archivelog
/oracle/product/10.2.0/db_1/bin/sqlplus "/ as sysdba" @delete_applied_redo_logs.sql
grep arc delete_applied_redo_logs.lst > delete_applied_redo_logs_1.sh
chmod 755 delete_applied_redo_logs_1.sh
sh delete_applied_redo_logs_1.sh
rm delete_applied_redo_logs_1.sh
rm delete_applied_redo_logs.lst
vals3:/home/oracle#cd /db/optima/archive/OPTPROD/archivelog
vals3:/db/optima/archive/OPTPROD/archivelog#cat delete_applied_redo_logs.sql
set echo off
set heading off
spool /db/optima/archive/OPTPROD/archivelog/delete_applied_redo_logs.lst
select 'rm -f ' || name from v$archived_log where applied = 'YES';
spool off
exit
vals3:/db/optima/archive/OPTPROD/archivelog#Hope That Helps.
Ogan -
Standby Redo Log Files and Directory Structure in Standby Site
Hi Guru's
I just want to confirm, i know that if the Directory structure is different i need to mention these 2 parameter in pfile
on primary site:
DB_CONVERT_DATAFILE='standby','primary'
LOG_CONVERT_DATAFILE='standby','primary'
On secondary Site:
DB_CONVERT_DATAFILE='primary','standby'
LOG_CONVERT_DATAFILE='primary','standby'
But i want to confirm this wheather i need to issue the complete path of the directory in both the above paramtere:
like:
DB_CONVERT_DATAFILE='/u01/oracle/app/oracle/oradata/standby','/u01/oracle/app/oracle/oradata/primary'
LOG_CONVERT_DATAFILE='/u01/oracle/app/oracle/oradata/standby','/u01/oracle/app/oracle/oradata/primary'
Second Confusion:-
After transferring Redo Standby log files created on primary and taken to standby on the above mentioned directory structure and after restoring the backup of primary db alongwith the standby control file will not impact the physical standby redo log placed on the above mentioned location.
Thanks in advance for your helpHello,
Regarding your 1st question, you need to provide the complete path and not just the directory name.
On the standby:
db_file_name_convert='<Full path of the datafiles on primary server>','<full path of the datafiles to be stored on the standby server>';
log_file_name_convert='<Full path of the redo logfiles on primary server>','<full path of the redo logfiles on the standby server>';
Second Confusion:-
After transferring Redo Standby log files created on primary and taken to standby on the above mentioned directory structure and after restoring the backup of primary db alongwith the standby control file will not impact the physical standby redo log placed on the above mentioned location.
How are you creating the standby database ? Using RMAN duplicate or through the restore/recovery options ?
You can create the standby redo logs later.
Regards,
Shivananda -
Why do we need standby redo log on Primary database.
Hi Gurus,
I was going through the document in OBE,
http://www.oracle.com/technology/obe/11gr1_db/ha/dataguard/physstby/physstdby.htm
I have two queries:
1) I noticed the statement -
"Configure the primary database to receive redo data, by adding the standby logfiles to the primary. "
Why do we have to create standby redo log on a primary database?
2) There is another statement --
"It is highly recommended that you have one more standby redo log group than you have online redo log groups as the primary database. The files must be the same size or larger than the primary database’s online redo logs. "
Why do we need one additional standby redo log group than in Primary database.
Could anyone please explain to me in simple words.
Thanks
Cherrish VaidiyanHi,
1. Standby redo logs are used only when the database_role is standby, it is recommended to be added in primary also so that they can be used on role reversal, however during normal working standby redo logs will not be used at all on primary.
2. In case of 3 online redo log groups, it is recommended to use 4 standby redo log group this is in case if log switching is happening frequently on primary and all 3 standby redo logs are still not completely archived on the standby and 4th can be used here as there will be some delay on standby due to network or slowness of arch on standby.
Use of the standby redo log groups depends on the redo generation rate, you can see only 2 standby redo logs are getting used while you have 4 standby redo log groups, when the redo generation rate is less.
So it is recommended to have one more standby redo log group when redo generation rate is high and all of the existing standby redo log group are getting used.
Regards
Anudeep
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Missing V2 records using Unserialized V3 deltas in Logistics
We have been experiencing missing Deltas in our Material Movement transactions feeding BW. This always occurs between 5:30AM and 6:00AM. When we examine the intermediate queues we notice the Deltas are not present in the V2 queue. I have read several
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Application doesn't even open!!
I have a lumia 520. Problem is that skype wont open in my mobile. I click on the icon but nothing happens. I have tried reinstalling many times. Please suggest me a solution.
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When Nokia PC suite is released to Linux-family op...
People are started to replace old Windows XP systems to new operating system (or planned to install near future) because everyone is telling that Windows Vista didn't work well even on new preinstalled system. Most of people I know are replaced their
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Where can get the adftutoial or adfdevguide for TopLink JPA with JSF/ADF ?
Hello... Can anyone suggest me where on OTN I can find the adftutorial and adfdevguide describing developement using Toplink JPA ( EJB 3.0) with JSF/ADF faces ? Thanking you in advance, Samba