RE: Backing up to a UNC path versus a local drive doesn't act the same

Hi

With UNC paths, backup up to the local machine, the traffic has to go to the
network re-director, down the TCP/IP stack, get turned around when it finds
the host, and go up the stack again. Totally expected.

File access on networks, compared to local disk access is very different at
API level.

Regards
--------------------------------
Mike Epprecht, Microsoft SQL Server MVP
Zurich, Switzerland

MVP Program: http://www.microsoft.com/mvp

Blog: http://www.msmvps.com/epprecht/



"Steen Persson" wrote:

> Hi
>
> I have just noticed a difference in how BACKUP works when I back up to a
> local drive versu when I do it to a UNC path.
> When I run the backup to a local drive, I can see that the .bak file gets
> created, but then stays a 0 Kb until the backup is finished. When it's
> finished, the .bak file is then being updated.
> If I then run the same backup to the same location, but specify the locati
on
> as e.g.  '\\Myserver\D$\MyBac
 kupFolder\MybackupFi
le.bak' it acts differentl
y.
> Now the file id being updated on the fly every 3-4 seconds. I also noticed
> that the latter takes significantly longer to complete the backup.
>
> I assume that there's a reason for this difference so does any of you know
> this reason? I have tried to look around so see if I could find something
> that describes this but with no luck. Not that it matters, but I'm just
> curious....:-).
>
> Regards
> Steen
>
>
>
>