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Subject: Re: multiple dumps to single tape
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On Tue, 16 Dec 2003 09:55 am, David Bear wrote:
> if I am writing multiple dumps to a single tape, is it wise to have mt
> write a setmark after dumping each file system?

There is no real need to do this.

If you want to write dump after dump onto a tape in the one session use the 
/dev/nsa0 device.  This device is the same as /dev/sa0 but doesnt rewind 
between sessions.  So the tape will be ready for the next dump automatically.  

If you are using the tape to archive data and want to write multiple dumps to 
tape over different sessions then you can position the tape drive to the end 
of the tape by using the mt eom command.  

Make sure that you note what sessions are on the tape so that you can use the 
mt fsf command to get the data off later.  Remember that mt fsf x goes 
forward x files, it doesnt go to x file.

As with everything important try it out first.  Nothing is worse than being 
bitten on the glaven by your own laziness with the hurting and the 
embarassment and the oy.