Networker

Re: [Networker] How NW cloning & multiplexing REALLY works

2007-01-25 10:20:54
Subject: Re: [Networker] How NW cloning & multiplexing REALLY works
From: David Dulek <ddulek AT FASTENAL DOT COM>
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Date: Thu, 25 Jan 2007 09:08:01 -0600
BUT ... Can you recover from a AFTD while also cloning from that device?

On Wednesday 24 January 2007 01:25, Preston de Guise wrote:
> Hi Curtis,
>
> >> I was just objecting to the fact that Davina said that Networker
> >> by design cannot do concurrent reads from disk as this limitation
> >> was removed in 7.3 up. Try to recover two or more savesets from
> >> the same AFTD and you will see them both happening at the
> >> same time.
> >> I did not claim that NW would do the cloning in parallell.
> >
> > Oh, so you're saying that NW can RECOVER two things at the same time.
> > That's cool.  It appears from the release notes that this only applies
> > to command line recoveries:
> >
> > "AFTD function now supports all concurrent recoveries by command line
> > clients. All save sets are recovered concurrently from AFTD by means of
> > a
> > command line operation."
> >
> > Am I interpreting that correctly?  In other words, if I did multiple GUI
> > restores, it wouldn't do the restores simultaneously?
>
> It wouldn't be the first time to have poorly written documentation :-)
>
> I believe that what this may be referring to is the capability of allowing
> clients to do restores without being storage nodes if the AFTDs are mounted
> in exactly the same path.
>
> That is, server has AFTD mounted at /d/01/nsr. Client also has it mounted
> at /d/01/nsr.
>
> In this new supported system, the client can, after quickly checking status
> with the owner of the AFTD, proceed with recovering the data without it
> going via the AFTD --- this does allow a large number of simultaneous
> restores indeed. The advantage of this mode is that if you're in an
> environment which requires a large number of restores it does reduce the
> load on the nsrmmd's.
>
> However, it is my understanding that multiple concurrent restores are
> supported without this mode ... and just testing on 2 different clients
> under 7.3.2 showed this to be correct.
>
> Cheers,
>
> Preston.

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