Re: [Networker] What are the barcode requirements for Networker

2012-10-31 06:53:13
Subject: Re: [Networker] What are the barcode requirements for Networker
From: Dag Nygren <dag AT NEWTECH DOT FI>
Date: Wed, 31 Oct 2012 12:40:22 +0200
On Wednesday 31 October 2012 09:12:57 Tony Albers wrote:
> I usually call the virtual tapes something like V00001L4 if I'm emulating 
> LTO4 tapes in my VTL. You might want to set vtapes the same size as your 
> physical tapes if you backup to vtl and clone to tape. Then you can even 
> match labels if you like i.e. V00002L4 has the same content as 00002L4.
> However, most vtl vendors recommend vtape sizes from 50 to 500 GB, since the 
> space in the vtl file system is not reclaimed until used vtapes are 
> relabeled. So the smaller your vtape, the faster it expires and the sooner it 
> is recycled.

As you are also emulating another downside of tapes with a VTL - Not being able 
to read and write at the same time, 
having maller tapes makes the probability smaller that we need the same tape 
for reading during the write as
smaller tape = less savesets.

> Furthermore, avoid creating too many unlabeled vtapes in the vtl since nw 
> will always label an unlabeled vtape instead of recycling one.
> So you could end up with an almost full vtl filesystem and still have 
> unlabeled tapes but no space to store data.

Is the behaviour on a VTL really different than in a normal jukebox on this 
one, Tony?
Cannot find anything in my docus on that and normally Networker always
prefers recyclable tapes to unlabeled ones.