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  • 15. Re: Can archivelog history in the v$table be full?
    yxes2013 Newbie
    Currently Being Moderated
    Thanks...
    So If one of my archivelogs got corrupted, I need to backtrack some steps to be able to startup the database, right? So if my archivelog is 1Gb theres a possibility that all the completeness check
    is contained in the archive. So this is the advantage of a big redo ;)
  • 16. Re: Can archivelog history in the v$table be full?
    Bawer Journeyer
    Currently Being Moderated
    yxes2013 wrote:
    @bawer
    What do you copy at midnight? flash_recovery_area or control+data files ?
    is there any scheduled rman task to backup database (daily or weekly) ?
    There is a schedule cron that shutdown db and copy datafiles and then startup db. the archive logs just retained where they are and deleted every week using "rm" and not rman delete.

    Edited by: yxes2013 on 14.2.2013 18:03
    You have a big problem!
    You don't use rman backup, what you do is a cold copy of database. You can't perform Point-In-Time Recovery. In case of failure, you can only recover your database to the time of shutdown. Your Archive-Logs aren't usable. To perform Recover with a SCN or Point-In-Time, you need ArchiveLogs, and archivelogs need a start backup created with rman (to restore the datafiles to a startpoint before failure and perform archivelogs, which recover command does)! If you don't use rman, you don't need set the database in ARCHIVELOG mode!
  • 17. Re: Can archivelog history in the v$table be full?
    yxes2013 Newbie
    Currently Being Moderated
    Yeah...I think I turned it off :) Since in history, we don't really do recover point in time. What I am concern is the crash recovery for the 1 day's transaction which I want it all accommodated in all the online redos. Can you comment on it?
  • 18. Re: Can archivelog history in the v$table be full?
    Hemant K Chitale Oracle ACE
    Currently Being Moderated
    You don't really need large Online Redo Logs for Instance (Crash) Recovery.

    Crash Recovery does work with small Online Redo Logs even if transactions are large.


    Hemant K Chitale
  • 19. Re: Can archivelog history in the v$table be full?
    yxes2013 Newbie
    Currently Being Moderated
    Thanks Hem,

    Hmmm I am confused....So if my database crashed for the day and I have a backup last night, + plus I have redos intact I do not have to worry lost transactions? even if I do not have archived logs?

    The scenario is like this:
    Archiving turned off.
    The system.dbf got removed accidentally or got corrupted.
    I need to restore from backups last night and recover the transactions for the day stored in the redos. Is it possible?
    I am thinking that all the online redo logs still holds all the transaction for the day.
  • 20. Re: Can archivelog history in the v$table be full?
    Hemant K Chitale Oracle ACE
    Currently Being Moderated
    You are talking of Media Recovery, not Crash Recovery.

    Yes, for Media Recovery you could use large Online Redo Logs.


    Hemant K Chitale
  • 21. Re: Can archivelog history in the v$table be full?
    Bawer Journeyer
    Currently Being Moderated
    yxes2013 wrote:
    Yeah...I think I turned it off :) Since in history, we don't really do recover point in time. What I am concern is the crash recovery for the 1 day's transaction which I want it all accommodated in all the online redos. Can you comment on it?
    If your business requirements doesn't need PTR, you can set database in NOARCHIVELOG mode.

    But RMAN is not used only to recover entire database! ;-)
    review http://docs.oracle.com/cd/E11882_01/backup.112/e10642/toc.htm
  • 22. Re: Can archivelog history in the v$table be full?
    Bawer Journeyer
    Currently Being Moderated
    yxes2013 wrote:
    Thanks Hem,

    Hmmm I am confused....So if my database crashed for the day and I have a backup last night, + plus I have redos intact I do not have to worry lost transactions? even if I do not have archived logs?

    The scenario is like this:
    Archiving turned off.
    The system.dbf got removed accidentally or got corrupted.
    I need to restore from backups last night and recover the transactions for the day stored in the redos. Is it possible?
    with NOARCHIVELOG mode, absolutely NO
    that is your big problem, if you want to recover the changes after a backup point, you need archivelogs with RMAN backups not the copies of data/control files, what you actually do!
  • 23. Re: Can archivelog history in the v$table be full?
    yxes2013 Newbie
    Currently Being Moderated
    Thanks baw,
    you need archivelogs with RMAN backups not the copies of data/control files, what you actually do!
    Assuming all the transaction for the day are all in the redos 1-10 such that I don not have archivelog. Can I recover it?

    Hemant said I can do media recovery. :P
  • 24. Re: Can archivelog history in the v$table be full?
    JohnWatson Guru
    Currently Being Moderated
    Bawer wrote:
    You don't use rman backup, what you do is a cold copy of database. You can't perform Point-In-Time Recovery. In case of failure, you can only recover your database to the time of shutdown. Your Archive-Logs aren't usable. To perform Recover with a SCN or Point-In-Time, you need ArchiveLogs, and archivelogs need a start backup created with rman (to restore the datafiles to a startpoint before failure and perform archivelogs, which recover command does)! If you don't use rman, you don't need set the database in ARCHIVELOG mode!
    This is not correct. Restore and recovery, with no loss of data, is straightforward and fully supported without using RMAN. Your cold backup plus the archivelogs plus the online logs are perfectly adequate.
    --
    John Watson
    Oracle Certified Master DBA
    http://skillbuilders.com
  • 25. Re: Can archivelog history in the v$table be full?
    yxes2013 Newbie
    Currently Being Moderated
    Thanks dear :)

    Note: I do not have archivelogs

    But If I restore the cold backup last night, I can still startup mount and recover database using backup controlfiles right? to apply the data in the online redologs.
  • 26. Re: Can archivelog history in the v$table be full?
    Bawer Journeyer
    Currently Being Moderated
    JohnWatson wrote:
    Bawer wrote:
    You don't use rman backup, what you do is a cold copy of database. You can't perform Point-In-Time Recovery. In case of failure, you can only recover your database to the time of shutdown. Your Archive-Logs aren't usable. To perform Recover with a SCN or Point-In-Time, you need ArchiveLogs, and archivelogs need a start backup created with rman (to restore the datafiles to a startpoint before failure and perform archivelogs, which recover command does)! If you don't use rman, you don't need set the database in ARCHIVELOG mode!
    This is not correct. Restore and recovery, with no loss of data, is straightforward and fully supported without using RMAN. Your cold backup plus the archivelogs plus the online logs are perfectly adequate.
    --
    John Watson
    Oracle Certified Master DBA
    http://skillbuilders.com
    this is interesting. please give more info about your suggestion.
  • 27. Re: Can archivelog history in the v$table be full?
    JohnWatson Guru
    Currently Being Moderated
    yxes2013 wrote:
    Thanks dear :)

    Note: I do not have archivelogs

    But If I restore the cold backup last night, I can still startup mount and recover database using backup controlfiles right? to apply the data in the online redologs.
    Going back to your oiriginal post.
    You said this:
    All the users go home after 6pm. So we shut down the database and perform tar all the /u01/oradata directory where all the data files are located.
    Then we delete all the archive logs.
    Your database is fully protected. If any datafile is damaged in the day, you can restore it from the previous evening's tar and apply all the archive logfiles generated since opening in the morning. The size of the online logfiles is not relevant.
    Then you said this:
    .since we do manual delete of the archivelogs (and not rman delete obsolete logs) this means in the data dictionary views all the logs are still recorded?
    I am afraid the data dictionary for archive logs will get full since we generate lots of logs everyday.
    The space for recording detail of archivelogs in the controlfile (not the data dictionary) is maintained automatically, you can see what is happening if you query v$controlfile_record_section.
    So you have no problem. Though you do need to read up on user-managed restore and recovery.
    --
    John Watson
    Oracle Certified Master DBA
    http://skillbuilders.com
  • 28. Re: Can archivelog history in the v$table be full?
    Bawer Journeyer
    Currently Being Moderated
    >
    If any datafile is damaged in the day, you can restore it from the previous evening's tar and apply all the archive logfiles generated since opening in the morning.
    How is this done? (apply the archive logfiles on cold copy)

    Edited by: Bawer on 15.02.2013 10:42
  • 29. Re: Can archivelog history in the v$table be full?
    JohnWatson Guru
    Currently Being Moderated
    Bawer wrote:
    >
    If any datafile is damaged in the day, you can restore it from the previous evening's tar and apply all the archive logfiles generated since opening in the morning.
    How is this done? (apply the archive logfiles on cold copy)

    Edited by: Bawer on 15.02.2013 10:42
    Rather than hijack OP's thread, perhaps open another topic asking for training on user managed restore and recovery?

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