Re: Separate ASM disk group for online redo log files?
From: mhoys <matthias.hoys_at_gmail.com>
Date: Mon, 11 Apr 2011 14:25:10 -0700 (PDT)
Message-ID: <ea3d3264-250b-42bc-8917-b53e2ea90767_at_l30g2000vbn.googlegroups.com>
On Apr 11, 3:55 pm, John Hurley <hurleyjo..._at_yahoo.com> wrote:
> Mathias:
>
> > Ok, I've read a lot about ASM recently :-)
>
> > In one of the technical papers from Oracle, they recommend to have
> > only 2 disk groups: one for the data files, and one for the recovery
> > files (FRA).
>
> I have 2 disk groups one separate for the online logs and the other
> one for everything else.
>
> I am NOT using an ASM based flash recovery area ... not using FRA at
> all. My archive logs go into a cooked file system.
>
> I was getting some really nasty funky problems early on trying to
> stress test system while using archive log mode going into ASM based
> FRA. It was a while back ... but I pretty quick immediately decided I
> really did not want to put all my eggs into the ASM basket.
>
> Disk based rman backups go into a cooked file system as do my archive
> logs.
>
> If something goes south with ASM and you pretty much lose
> everything ... and your backups were inside ASM ... what are you going
> to do?
>
> When using ASM for the database and testing recoveries ... one option
> ( which really really needs to be tested and documented ) is starting
> back at the beginning by recreating the ASM disk groups ... ( create
> diskgroup blah blah blah FORCE ) ... which also means you are then
> going to restore a controlfile backup next ).
Date: Mon, 11 Apr 2011 14:25:10 -0700 (PDT)
Message-ID: <ea3d3264-250b-42bc-8917-b53e2ea90767_at_l30g2000vbn.googlegroups.com>
On Apr 11, 3:55 pm, John Hurley <hurleyjo..._at_yahoo.com> wrote:
> Mathias:
>
> > Ok, I've read a lot about ASM recently :-)
>
> > In one of the technical papers from Oracle, they recommend to have
> > only 2 disk groups: one for the data files, and one for the recovery
> > files (FRA).
>
> I have 2 disk groups one separate for the online logs and the other
> one for everything else.
>
> I am NOT using an ASM based flash recovery area ... not using FRA at
> all. My archive logs go into a cooked file system.
>
> I was getting some really nasty funky problems early on trying to
> stress test system while using archive log mode going into ASM based
> FRA. It was a while back ... but I pretty quick immediately decided I
> really did not want to put all my eggs into the ASM basket.
>
> Disk based rman backups go into a cooked file system as do my archive
> logs.
>
> If something goes south with ASM and you pretty much lose
> everything ... and your backups were inside ASM ... what are you going
> to do?
>
> When using ASM for the database and testing recoveries ... one option
> ( which really really needs to be tested and documented ) is starting
> back at the beginning by recreating the ASM disk groups ... ( create
> diskgroup blah blah blah FORCE ) ... which also means you are then
> going to restore a controlfile backup next ).
Hello John,
Interesting idea of using ASM only for the "data" files and a cooked
file system for the FRA...
I just realised that we first do a backup on disk and then the backup
software writes the backup files from disk to tape. That would
probably be not possible with ASM as file system, anyway.
Matthias Received on Mon Apr 11 2011 - 16:25:10 CDT