RE: Recovery with logs, then incremental, then more logs?

From: Khemmanivanh, Somckit <somckit.khemmanivanh_at_weyerhaeuser.com>
Date: Tue, 18 Apr 2006 15:39:07 -0700
Message-ID: <65C0D8935651CB4D96E97CEFAC5A12B9022F0ED6@wafedixm10.corp.weyer.pri>

Could there be some buffering of the writes involved here? i.e. The OS writes to an FS cache and gives the all clear to lgwr but the write never makes it to disk?

Thanks!
-----Original Message-----
From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Riyaj Shamsudeen Sent: Tuesday, April 18, 2006 3:10 PM
To: Allen, Brandon
Cc: oracle-l_at_freelists.org
Subject: Re: Recovery with logs, then incremental, then more logs?

Issuing a commit forces the LGWR to write the log buffer contents to disk physically, which is a primary mechanism for database consistency.

After the successful write, committed changes are permanent whether instance crashes or not later. From your error message, I think that *somehow* log writes are partly successful leading to corruption.

It is scary to have redo log corruption just due to out-of-space errors..

I don't know much about NFS3 protocol, but is your vendor / file system in this list ?

http://www.oracle.com/technology/deploy/availability/htdocs/vendors_nfs. html

Allen, Brandon wrote:
> It is NFS3 - details below:
>
>
> /baan4 ->mount|grep -e mounted -e --- -e baan4db
> node mounted mounted over vfs date
options
> -------- --------------- --------------- ------ ------------

---

> gbtnas01 /baan4db /baan4 nfs3 Feb 12 21:29
rw,bg,hard,intr,rsize=8192,wsize=8192,vers=3,proto=tcp,biods=24
>
>
> Please let me know if you see any problems with the above config.
>
> Thanks,
> Brandon
>
>
> -----Original Message-----
> From: Riyaj Shamsudeen [mailto:rshamsud_at_jcpenney.com]
> Sent: Tuesday, April 18, 2006 12:14 PM
> To: Allen, Brandon
> Cc: Binley Lim; oracle-l_at_freelists.org
> Subject: Re: Recovery with logs, then incremental, then more logs?
>
>
> What type of file system are you using for your redo log files ?
Is there any special mount options in use ? While I agree with the solution as point-in-time recovery for online redo log corruption, but out-of-space error as a cause, does not fit for redo log files.
>
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>
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Received on Tue Apr 18 2006 - 17:39:07 CDT