Comparision between Multimaster replication and data guard

Hi,
I have some questions regarding Multimaster Replication and Data Guard. Like
*1.)* I have a web site having database in oracle 10.2.0 and multimaster replication configured on it. But whenever i need to change the structure of the tables i
need to stop replication. So my web site is unavailable but my first priority is availability. So will it be useful for me to configure data guard.
*2.)* I have configured data guard for testing . My Database is Named as Gard and physical standby database is like stan.
it is working fine.
suppose my main database server get corrupted i have no option to start main database server. Now i left with only standby server how i can start standby server
as database main server.
*3.)* Is there any if main database stop working Standby database start working as main without dba intervention.
Thanks
Umesh
Edited by: Umesh Sharma on Jan 14, 2009 4:17 AM

Hi Umesh,
first of all you should be aware that Dataguard and Replication are two completely different things.
While the database where you replicate to is always up and open in read write mode, a physical standby can either be recovering or open in read only mode.
1.) I think from what you are telling you probably should consider using dataguard with a logical standby database, but be aware that there will be some limitations regarding datatypes.
2.) you can do a failover or a switchover, depending on your database version switchback may not be possible
3.) have a look at dataguard broker, you can use it to automate the failover
Best regards,
PP

Similar Messages

Difference between Manual Standby and Data Guard Broker..

hi,
could any let me know any usefull docs which help to understand the difference between manual dr and data guard broker?
thanks,

>
could any let me know any usefull docs which help to understand the difference between manual dr and data guard broker?
>
Without Data Guard Broker:
http://www.oracle.com/pls/db112/to_toc?pathname=server.112/e17022/toc.htm
With Data Guard Broker:
http://www.oracle.com/pls/db112/to_toc?pathname=server.112/e17023/toc.htm
See especially why you want to use the broker:
http://download.oracle.com/docs/cd/E11882_01/server.112/e17023/concepts.htm#i1013106
In short: You should have a good reason if you do not use the broker, because it is the officially recommended way to maintain Data Guard. It is even required for some features like Fast-Start Failover.
Kind regards
Uwe Hesse
http://uhesse.wordpress.com

Diff between WAN replication and MAN replication

Hi All,
Kinldy tell me differnece between WAN replication and MAN replication in cluster in weblogic server.
Thanks in advance.
Balaji kumar

MAN replication uses in-memory replication to keep the primary and secondary copies of the session
on different clusters. It always attempts to locate the secondary session on the remote cluster.
If connectivity between the data centers is lost, the local cluster will replicate the session within
the cluster. On the first request for the session once inter data center connectivity is restored, WebLogic
Server will relocate the session’s secondary to the remote cluster.
WAN replication uses in-memory replication within the primary cluster and asynchronous
replication via a database to keep a third copy of the session at the remote data center.
The database-backed replication mechanism makes the session data available to the other data center's
cluster should data centerlevel failover occur. The local server buffers its primary session updates in
an in-memory buffer that is periodically flushed. The database-backed replication has two modes of
operation:
- Local cluster periodically flushed the in-memory buffer to its local database. Cross data center
replication is handled externally using some sort of database level replication technology
of your choosing.
- Local cluster uses RMI to push updates periodically from the in-memory buffer to the
remote cluster. The remote cluster writes these updates to its local database.

Different between initial replication and delta replication

Hi,
What is different between initial replication and delta replication of the catalog to B2B?
Denis Khveshchenik

Initial replication will replicate the full catalog
Delta replication - The replication will be based on teh change pointer that have been updated, so only the items that have been changed since the last initial replication will be replicated. This should result in a quicker replication time.

Difference between relational integrity and data intigrity

hi
could anybody tell me
what is the difference between
relational integrity and data intigrity
tahnx
kals.

hi,
Data Integrity
Data integrity means, in part, that you can correctly and consistently navigate and manipulate the tables in the database. There are two basic rules to ensure data integrity; entity integrity and referential integrity.
The entity integrity rule states that the value of the primary key can never be a null value (a null value is one that has no value and is not the same as a blank). Because a primary key is used to identify a unique row in a relational table, its value must always be specified and should never be unknown. The integrity rule requires that insert, update, and delete operations maintain the uniqueness and existence of all primary keys.
The referential integrity rule states that if a relational table has a foreign key, then every value of the foreign key must either be null or match the values in the relational table in which that foreign key is a primary key.
What is a Relational Integrity?
A relational database contains tables of data which are related to each other. For example, articles are related to the author who wrote them, and conversely, authors are related to the articles they wrote. (Sounds obvious, and it is.) That's the relational part.
When we work with a relational database, we naturally expect that data in related tables stay related. For example, articles written by MartinB should always be related to MartinB and never be confused with articles written by any other author. That's the integrity part.
Relational Integrity is also called Referential Integrity, perhaps because the mechanism for ensuring integrity is implemented by the way the tables reference each other. Both terms are okay with me. I usually just say RI anyway.
Regards,
Sourabh

Difference between physical standby database and Data Guard

Hi guys,
Today I attended one interview. They asked me a difference between the Oracle Physical Standby database and Oracle Dataguard?
Upto my knowledge Oracle Physical Standby Database is one type of Standby Database can be configured using Oracle Databaguard Feature.
Can you people calrify me on this.
Regards,
Vijayaraghavan K

hello,
yes you are right upto some extent...here is para form oracle doc
Oracle Data Guard is the most effective and comprehensive
data availability, data protection, and disaster recovery solution
for enterprise databases. It provides the management, monitoring,
and automation software infrastructure to create and maintain one
or more synchronized standby databases to protect data from failures,
disasters, errors, and corruptions.
Data Guard standby databases can be located at remote disaster
recovery sites thousands of miles away from the production data center,
or they may be located in the same city, same campus,
or even in the same building. If the production database
becomes unavailable because of a planned or an unplanned outage,
Data Guard can switch any standby database to the production role,
thus minimizing downtime and preventing any data loss.oracle data guard is maximum availiblity solution which maintain physical standby databases and in case of failure of production can switch production role to and standby database.
read it here
http://www.oracle.com/technology/deploy/availability/htdocs/DataGuardOverview.html
thanks and regards
VD
Edited by: Dixit on Aug 31, 2009 1:35 AM
Edited by: Dixit on Aug 31, 2009 1:36 AM

Supplemental logging with Oracle 10gR2 Streams and Data Guard

Hello,
I have a environment with Oracle DB 10gR2 and Physical Standby with Data Guard DR Conf. Right now, this environment is going to be extended to a replication schema using 2-way Oracle Streams Replication (for replication to the central office from this branch office, other branchs will be added soon). The primary DB will be replicated to the other primary DB (in the remote central office).
So, there is my question: It's completly necesary to specify Supplemental Logging on the sources databases (primaries) for setting 2-way Streams Replication?, and, if it's completly necesary, then, do I can set Supplemental Logging on primaries without affect theirs physical standbys, or do I need to do something special?
Thanks in advance.

Sorry, it's repeated. 'cus browser connection problem.

Grid Control and Data Guard Setup

Hi,
I have 4 PCs on which I wish to test the following:
1. OEM Grid Control 10.2 - Console + Service + Agent
2. Data Guard feature with Broker
3. Standby Setup for a Primary Database.
I will create the Primary DB on one Linux PC.
Standby DB using Grid Control & DataGuard on second Linux PC.
The Third PC is also Linux but the fourth PC is Windows XP.
Please guide me in understanding the following:
1. On which PCs should I install OEM Grid Control 10.2 - Console + Service + Agent?
2. On which PC should I setup DB Broker?
Please assume that I will use Oracle 10.2 Softwares and Linux x86 version.
Regards

well why don't you go ahead and test?!
Test and see whether you want to put oms, console all one machine, or whether you want to separate out the componests (you'll need an agent on each box regardless). I have no idea what the specs of your machines are, so why don't read the documentation on Grid and dataguard, see what the recommended settings are and then plan what you want to do.
Bazza

Grid control agent and data guard in mount mode

Hello,
I would like to know how you manage your data guards when you do not have the license for active data guard with the grid control agents. The standby database is in mount mode, so the agents cannot query the database.
What do you guys do in such cases? Remove the agent? Or wait till a switchover?

Check this out with a mounted database
[lo***p02].oracle:/home/oracle > sqlplus dbsnmp
SQL*Plus: Release 11.2.0.3.0 Production on Mon Jun 4 15:52:11 2012
Copyright (c) 1982, 2011, Oracle. All rights reserved.
Enter password:
ERROR:
ORA-01033: ORACLE initialization or shutdown in progress
Process ID: 0
Session ID: 0 Serial number: 0It cannot connect.
And then
[lo****p02].oracle:/home/oracle > sqlplus / as sysdba
SQL*Plus: Release 11.2.0.3.0 Production on Mon Jun 4 15:57:49 2012
Copyright (c) 1982, 2011, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,
Data Mining and Real Application Testing options
SQL> select open_mode from v$database;
OPEN_MODE
MOUNTED

Sql Developer and Data Guard enabled instance

I have version 1.1.2.25 SQL Developer and when I try to connect to Oracle 10gR2 instance which is data guard enabled and its logical standby it spits few message, and then connects, but data is not visible from any table.
Is there any way to see data and other code while in logical standby instance which only in read only mode?
Thanks.

This problem came when I tried to connect to Oracle
instance which is a logical standby in data guard
setup. Eventually connection is made and then you can
not see any object.
In logical standby database its suppose to be read
only and should be available for query.
In TOAD you can see every thing and when you want to
make any change ,it spits an error and wouldn't allow
you to make any change.
My question was, why SQL Developer is not showing the
objects in the list and its contains.Perhaps we could help you if you told us what the error was.

Database Smart Flash Cache and Data Guard

We are on Oracle 11.2.0.2 on OEL 5 and our considering buying fusion io (PCIe flash drives) for our Production (Primary) database.
My question is; Can we use Physical Data Guard with the Primary side using Database Smart Flash Cache and keep-ing tables and/or partitions in the Flash Cache and have a Standby side that does not have Database Smart Flash Cache?

Yes you can.
Data Guard will not check what type drive you are using. As long as you meet the database and network requirements it will work.
http://www.oracle.com/technetwork/database/features/availability/maa-090890.html
Check out these white papers if you have concerns
"Migration to Automatic Storage Management (ASM)"
"Best Practices for Creating a Low-Cost Storage Grid for Oracle Databases"
In addition here's an example of using two different file systems with Data Guard
http://pythianpang.wordpress.com/2009/07/07/data-guard-asm-primary-to-filesystem-physical-standby-using-rman-duplicate/
Best Regards
mseberg

Cardinality between Message Type and Data Type

Hi SAP gurus,
Could anyone please tell me the cardinality between the Message Type and Data Type?
Thanks,
Adnan Abbasi

1:1
Sameer

Can streams and data guard run together

I need to set up a staging database to run streams from.
Can I use data guard from the production database to the staging database and
streams on top of that?
Has anyone done this?

Correction:
Data Guard Redo Apply can be used to provide high availability/disaster recovery for a Streams database. For best practices using Dataguard Redo Apply with Streams, see http://www.oracle.com/technology/deploy/availability/pdf/MAA_WP_10gDataGuardRoleTransitionsStreams.pdf
Data Guard SQL Apply cannot be used to provide high availability/disaster recovery for a Streams database.

Sharing a Time Capsule between Time Machine and Data Storage

I currently have a MBP with a 120 GB hard drive that is busting at the seams. I have a 500 GB time capsule which I use Time Machine on. I am going to move iphoto and itunes libraries onto an external drive and I was wondering whether I can share the Time Capsule between TM backup and being an external drive. It currently has more than 325 GB available. Appreciate any advice.

alastairandnicole wrote:
Sorry, I'm not that Mac literate. My plan was to connect the WD Book external hard drive by USB to the Time Capsule so that it will wirelessly mount. Will TM back that up automatically?
No TM will not back up network drives. as I said it has to be directly attached. if you attach the drive to the computer instead of the TC, TM will back it up.

Difference between Data Replication and Data Synchronization?

Hi Brian: Sorry, the Data Replication task wizard does not support ODBC sources. I don't think there's an easy way to truncate the target tables using a Data Synchronization task, but you should be able to read data from an ODBC source and write it to your target. The main difference between the two task wizards:Data Replication allows you to copy multiple tables from the same source and do incremental loads (only copying new or updated data on subsequent runs of the same task)Data Syncronization allows you to transform data with field expressions and lookups. Cheers,Josh

I typically use Data Replication where I truncate the target, but it doesn't appear that this works for ODBC connections. However, Data Sync does work for ODBC connections--if I'm already truncating the target, is this the same as a data sync

Comparision between Multimaster replication and data guard

Similar Messages

Maybe you are looking for