chris.blackmor at amd
Jun 25, 2002, 7:22 AM
Post #2 of 2
(750 views)
Permalink
|
On Mon, Jun 24, 2002 at 08:12:50PM -0700, Art Hebert wrote:
>
>
> Having never been able to to attend Netapp classes, bear with me if these
> are fairly simple.
>
> 1) CIFS was purchased but never actually used. It currently shows up when
> you type license.
> Will this in anyway affect the Netapp nfs performance?
Shouldn't.
If you aren't using it it should just be a licensed feature.
>
> 2) Does disk scrubbing run automatically daily and if so is this
> changeable, by day, by time?
Scrub is every Sunday morning at 1am.
You cannot change the date and time on the automatic scrub BUT
you CAN turn scrubbing off and scrub using a cron job to start
the scrub.
>
> 3) Can somebody give me the rundown on running wack? This is what I have
> off the net (somehow the
> this is how you do it part never got published).
wack is now called wafl_check.
You have to take the volume offline to run this.
The only time I have ever had to run this is on advice from NetApp support.
Good info from Dave Hitz.
>
> When to use WACK on a NetApp Filer
> >From an email by Dave Hitz (12/1999) on the Toasters mailing list.
> The main difference between "wack" and fsck or scandisk is that you
> shouldn't need to run wack during normal operation.
> In particular, unlike UNIX and NT, you don't need to run "wack" after a
> system panic, or when you pull the plug without shutting the system down, or
> after a power failure. The WAFL filesystem uses a database technique called
> "shadow paging with NV-RAM log replay" to maintain a fully consistent state
> on disk even in the face of unexpected shutdowns.
> So when do you need to run wack? Suppose that you have a disk fail in RAID,
> and then when you try to reconstruct the data from the lost disk you
> discover that there is a bad sector on one of the other drives. Most of your
> file system data is just fine, but you've got a couple of blocks that can't
> be recovered. The RAID subsystem zeros both blocks, since that's the best
> that you can do, but now you need to run wack in order to fix things up, in
> case the zeroed blocks contained file system data like inodes, indirect
> blocks, or the free block map.
> And yes, I must confess that like any computer, NetApp systems do contain
> the occasional bug, so WAFL has a number of checks to make sure that the
> on-disk data looks reasonable, and if it finds a problem it will ask you to
> perform a wack.
> Our goal is for customers never to need to run wack, but the reality is that
> people sometimes do need to use it. this is how you do it.
>
> Thanks
>
> art hebert
>
>
>
--
-----------------------------------------------------------------------------
* Chris Blackmor _______ | There's only three things *
* Advanced Micro Devices \____ | | thats for sure..... *
* Phone: (512) 602-1608 /| | | | taxes, death, and trouble *
* Fax: (512) 602-5155 | |___| | | Rickie Lee Jones *
* Email: chris.blackmor [at] amd |____/ \| | "Trouble Man" *
-----------------------------------------------------------------------------
* My comments are mine, and mine alone. *
-----------------------------------------------------------------------------
|
