Re: [Networker] strange tape writing stats

        I don't see any harware problem though the one tape drive
dedicated to backup our netapp has fine compression.  I've been
to see if a specific group of tape deives are the problem (we have 7
in our Qualstar jukebox) but it doesn't seem so.  Also, in the past
I had tis problem and it would get mutch better, though not go
away.  As of now, some tapes seem reasonable but most get 49 or
50 GIG.
        Per someone on the lists suggestion (I forget who) I'm using
tar to write to each tape drive a bunch of null filled files to see
if at least that gets compression

Paul

On Thu, 8 Aug 2002, Scott Kampen wrote:

> Date: Thu, 8 Aug 2002 11:42:07 -0700
> From: Scott Kampen <SKampen AT VERISIGN DOT COM>
> Reply-To: Legato NetWorker discussion <NETWORKER AT LISTMAIL.TEMPLE DOT EDU>,
     Scott Kampen <SKampen AT VERISIGN DOT COM>
> To: NETWORKER AT LISTMAIL.TEMPLE DOT EDU
> Subject: Re: [Networker] strange tape writing stats
>
> Up until the end of June we were getting anywhere from 80 to 300 gigs per
> tape (AIT2).  Then all of a sudden tapes started filling up at 49gigs.  This
> has been a problem since the amount of tapes I need to purchase each week
> has now increased dramatically.  I'm investing whether there is some sort of
> hardware issue going on, but so far everything looks fine.
>
> -----Original Message-----
> From: Maiello, Robert [mailto:Robert.Maiello AT MEDEC DOT COM]
> Sent: Thursday, August 08, 2002 8:50 AM
> To: NETWORKER AT LISTMAIL.TEMPLE DOT EDU
> Subject: Re: [Networker] strange tape writing stats
>
>
> No, our compression is pretty good.  With our already compressed
> novell data we used to get 35GB on a DLT7000 tape.  We get 100 GB on
> a tape now.
>
> With other compressable data we've seen 300+ on a tape.
>
> Make sure you have the correct quantum line in your st.conf?  I'm using:
>
> ##### DLT7000s and SDLT support #########
> DLT7k-data      =       1,0x38,0,0xD639,4,0x82,0x83,0x84,0x85,2;
> SDLT1           =       1,0x38,0,0x19639,4,0x90,0x91,0x90,0x91,3;
>
>
> Umm, of course, I forgot LTO was called out here, not SDLT.
>
> Robert Maiello
> Thomson
> Medical Economics
>
>
>  -----Original Message-----
> From:   Paul T. DAY [mailto:day AT deas.harvard DOT edu]
> Sent:   Thursday, August 08, 2002 10:22 AM
> To:     robert.maiello AT MEDEC DOT COM; howard.martin AT eds DOT com;
> NETWORKER AT LISTMAIL.TEMPLE DOT EDU
> Cc:     Paul T. DAY
> Subject:        Re: [Networker] strange tape writing stats
>
>         Does anybody have problems with compression.  Its worse sometioms
> (almost all tapes just use the rated 50G) and then gets better for a
> while.
>
> Paul
> >
> > Date: Thu, 8 Aug 2002 03:51:26 -0400
> > From: Howard Martin <howard.martin AT EDS DOT COM>
> > Reply-To: Legato NetWorker discussion <NETWORKER AT LISTMAIL.TEMPLE DOT 
> > EDU>,
> >      Howard Martin <howard.martin AT EDS DOT COM>
> > To: NETWORKER AT LISTMAIL.TEMPLE DOT EDU
> > Subject: Re: [Networker] strange tape writing stats
> >
> > I've hit the same problem.
> > NetWorker 6.1.1.Build.238 Enerprise Edition
> > SunOS 5.7 E450
> > DLT7000 and IBM LTO
> > I find the nwadmin GUI under reports speeds by around 25% , the response
> > from our Legato support company was that this was due to networker not
> > polling the drives frequently, to increase the polling rate and improve
> > accuracy was considered unlikely to be a high priority for Legato but I'm
> > going to ask that a RFE is rasied for it.
> >
> >
> > On Wed, 7 Aug 2002 13:26:07 -0400, Paul T. DAY <day AT DEAS.HARVARD DOT EDU>
> wrote:
> >
> > >        When I look in nwadmin/nsrwatch, I see writing at about 4.5
> meg/hr
> > >yet when I do an iostat I see it writing/reading at just over 6 megs/hr.
> > >Is this normal.  I also don't seem to be getting much compresion most of
> > >the time.  Any ideas.
> > >
> > >NetWorker 6.1.1.Build.238 Power/110
> > >SunOS nsrhost 5.8 Generic_108528-05 sun4u sparc SUNW,Ultra-80
> > >Qualstar library with 7 AIT-2 drives
> > >
> > >Paul
>
>
> ________________________________________________________________________
> This email has been scanned for all viruses by the MessageLabs SkyScan
> service.
> ________________________________________________________________________
>
>
> ________________________________________________________________________
>
> --
> Note: To sign off this list, send a "signoff" command via email
> to listserv AT listmail.temple DOT edu or visit the list's Web site at
> http://listmail.temple.edu/archives/networker.html where you can
> also view and post messages to the list.
> =*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=
> The information contained in this communication may be confidential or
> legally privileged and is intended only for the recipient named above. If
> the reader of this message is not the intended recipient, you are hereby
> notified that any dissemination, distribution or copying of this
> communication or its contents is strictly prohibited. If you have received
> this communication in error, please immediately advise the sender and delete
> the original and any copies from your computer system.
>
> --
> Note: To sign off this list, send a "signoff" command via email
> to listserv AT listmail.temple DOT edu or visit the list's Web site at
> http://listmail.temple.edu/archives/networker.html where you can
> also view and post messages to the list.
> =*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=
>
>
>

--
Note: To sign off this list, send a "signoff" command via email
to listserv AT listmail.temple DOT edu or visit the list's Web site at
http://listmail.temple.edu/archives/networker.html where you can
also view and post messages to the list.
=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=