Re: [Networker] Fw: [Networker] Parallelism of "backup clone" pool devices?

2008-05-29 14:44:54
Subject: Re: [Networker] Fw: [Networker] Parallelism of "backup clone" pool devices?
From: Curtis Preston <cpreston AT GLASSHOUSE DOT COM>
Date: Thu, 29 May 2008 14:34:26 -0400
Davina said:

>Clone jobs are single-threaded - that is correct. One session at a
>requiring one drive to read and one drive to write.

Correct.  In order for 5 jobs to use 4 drives, at least two jobs would
have to multiplex each other's backups onto a single tape drive, which
definitely cannot/will not happen.  NW can multiplex backups from
multiple sources to a single drive, but cannot multiplex clone jobs from
multiple sources to a single drive.

This is not to say that when you are cloning a multiplexed backup, it
will demultiplex it.  That is a commonly held misconception.  You can
FORCE it to do that, but the default is to preserve multiplexing when

I covered this in a blog post a while ago:

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