1. Get rid of all advertisements and get unlimited access to documents by upgrading to Premium Membership. Upgrade to Premium Now and also get a Premium Badge!

Data guard strategy

Discussion in 'Security, Backup and Recovery' started by aaaaaarko, Mar 13, 2012.

  1. aaaaaarko

    aaaaaarko Active Member

    Messages:
    4
    Likes Received:
    0
    Trophy Points:
    55
    I have oracle 10g R2 installed in the server which runs 10am to 5pm daily.I want to implement Data guard only for switch-over purpose at the time of modification of primary database.But i am not sure whether data guard can be implemented on a server which shuts down daily.Kindly say whether is it possible to implement dataguard on this server and how?
     
  2. zargon

    zargon Community Moderator Forum Guru

    Messages:
    2,351
    Likes Received:
    348
    Trophy Points:
    1,430
    Location:
    Aurora, CO
    It is possible; it may not be recommended depending upon the data volume processed in the primary database as it will take time to catch up from the previous night's transactions. That being said you simply iimplement Data Guard as a physical standby database on the desired server.

    Again, remember it will take time to catch up from the nights activities on the priimary once the standby starts in the morning.
     
  3. aaaaaarko

    aaaaaarko Active Member

    Messages:
    4
    Likes Received:
    0
    Trophy Points:
    55
    both the primary and secondary database will run 10 am to 5 pm.In this circumstances it might not be taken much time to catch up the data from primary server.
     
  4. zargon

    zargon Community Moderator Forum Guru

    Messages:
    2,351
    Likes Received:
    348
    Trophy Points:
    1,430
    Location:
    Aurora, CO
    No, it won't. You should be fine if you perform a log switch before shutting down the primary and give the system a few minutes to transfer the file to the secondary.
     
  5. aaaaaarko

    aaaaaarko Active Member

    Messages:
    4
    Likes Received:
    0
    Trophy Points:
    55
    Thanx Zargon.It will be helpful if you can suggest which protection mode should i run the data guard?
     
  6. zargon

    zargon Community Moderator Forum Guru

    Messages:
    2,351
    Likes Received:
    348
    Trophy Points:
    1,430
    Location:
    Aurora, CO
    That depends upon how 'tied' you want to be to the primary:

    Data Guard provides a mechanism whereby Oracle will keep one or more databases synchronized with the primary database. For a physical standby configuration in release 10.2 three protection modes are available

    Maximum Protection
    Maximum Availability
    Maximum Performance

    Maximum Protection mode guarantees that the standby will be in 'lock step' with the primary as all transactions are written to both the primary redo logs and the standby redo logs with the caveat that if Oracle cannot write a transaction to the standby redo logs the primary will suspend activity until the error causing the write issue is corrected. No transasction can commit until all local and remote redo has been written successfully. This ensures a seamless cutover should a disaster strike, but it also inconveniences production users should problems in standby redo log writes occur. Maximum Availability mode works like Maximum Protection mode until a standby redo log write problem occurs, when Oracle switches to Maximum Performance mode until the standby redo log write issue is resolved, at which time the standby redo log writes catch up with the primary. Maximum Performance mode allows a transaction to commit after successfully writing the redo entries to the local redo logs regardless of whether the standby redo log writes have completed.

    My choice would be Maximum Performance mode.