ADSM-L

Re: [ADSM-L] Tape library possible replacement - push/pull

2013-02-04 15:49:21
Subject: Re: [ADSM-L] Tape library possible replacement - push/pull
From: Richard Rhodes <rrhodes AT FIRSTENERGYCORP DOT COM>
To: ADSM-L AT VM.MARIST DOT EDU
Date: Mon, 4 Feb 2013 15:35:46 -0500
Your going to miss some aspects of your 3494 . . . .

Here's how I understand things.

The 3584 library is a SCSI library.  As tape libraries began to multiply
there was a need to make access to them easier.  It made no sense to have
every tape library vendor create a unique interface, which every backup
software vendor would then have to support.  The solution was to extend
the SCSI standard to include tape libraries - a common set of scsi
commands to manage/manipulate a library. This was back in the days of fat
parallel scsi cabling (scsi as in device interconnection, as opposed to
scsi the protocol).  Instead of the 3494 IP connection to access the
library, the library is accessed across the SCSI connection.    Fibre
channel came around as a new interconnect interface, but it runs the same
(mostly/somewhat)  scsi protocol.

(3494 librarys use TCP/IP to access the library, and STK libraries use
ALSM.  All other libraries that I know of are SCSI libraries.)

In a SCSI library  every slot, robot, tape drive and door slot has a
address - the element address.  Below are some of the element addresses
for one of our 3584 libraries: (tsm "show slots" cmd)

(some drive)
Drive   0, element 258
Drive   1, element 259
Drive   2, element 260
Drive   3, element 261
<snip>

(the robot)
Changer 0, element 1
Changer 1, element 2

(the cap door slots)
ImpExp 0, element number 769
ImpExp 1, element number 770
ImpExp 2, element number 771
ImpExp 3, element number 772
<snip>

(regular slots with tapes)
Slot 0, status Allocated, element number 1025, barcode not present,
barcode value <>, devT=3592, mediaT=411, elemT=ANY
Slot 1, status Allocated, element number 1026, barcode not present,
barcode value <>, devT=3592, mediaT=411, elemT=ANY
Slot 2, status Allocated, element number 1027, barcode not present,
barcode value <>, devT=3592, mediaT=411, elemT=ANY
Slot 3, status Allocated, element number 1028, barcode not present,
barcode value <>, devT=3592, mediaT=411, elemT=ANY
Slot 4, status Allocated, element number 1029, barcode not present,
barcode value <>, devT=3592, mediaT=411, elemT=ANY
Slot 5, status Allocated, element number 1030, barcode not present,
barcode value <>, devT=3592, mediaT=411, elemT=ANY
Slot 6, status Allocated, element number 1031, barcode not present,
barcode value <>, devT=3592, mediaT=411, elemT=ANY
Slot 7, status Allocated, element number 1032, barcode not present,
barcode value <>, devT=3592, mediaT=411, elemT=ANY
<snip>

When you run a inventory of the library, the library gives TSM this list,
showing TSM what tape barcode is in each slot.   TSM keeps this list in
It's database.   Here is a "q libvol" listing - not the element address of
each tape.


Library Name Volume Name Status           Owner      Last Use  Home Device
                                                               Element
Type
------------ ----------- ---------------- ---------- --------- -------
------
3584ISOC     J00000      Private          TSMSAP1    Data      1,253 3592
3584ISOC     J00001      Private          TSMSAP1    Data      1,041 3592
3584ISOC     J00002      Private          TSMSAP2    Data      1,046 3592
3584ISOC     J00003      Private          TSM6       Data      1,060 3592
3584ISOC     J00004      Private          TSMSAP1    Data      1,249 3592
3584ISOC     J00005      Private          TSM1       Data      1,248 3592


 When TSM requests a mount to a SCSI tape library, it asks the library to
move a tape from element address X to element address Y.  For example from
the above - to mount tape J00000 into drive 0 it would send a SCSI command
that requeste the library to move element address 1253 to element address
258.

If the two get out of sync, then you have to ask tsm to get a new list.
GRRRRRRRR.

The 3494 can have two processors (OS2 pc's, I believe), and the TSM drives
can be given both for failover. In the SCSI library you tell the library
to put a control on several drives, which show up as separate LUN's in the
operating system, and the Atape drives can be configured for failover. YOu
tell TSM one LUN (in AIX they are RMT devices), and Atape will will send
the requests to one of the several paths/devices.  Similar to disk
multi-pathing.

The LAN interface to the library is for a Web GUI.  There is also a java
CLI interface that is available, but unsupported.  I've never been able to
get it to work.  IBM had Tape utilities with the driver that let you do
stuff against the library also.

Just some thoughts  . . .

Rick






From:   Zoltan Forray <zforray AT VCU DOT EDU>
To:     ADSM-L AT VM.MARIST DOT EDU
Date:   02/04/2013 01:47 PM
Subject:        Re: Tape library possible replacement - push/pull
Sent by:        "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>



As this project moves forward, I am doing more and more research since I
am
unfamiliar with this beast (3494 has been my baby since it was installed
in
1995).

The book talks about "*to communicate with a server, the IBM System
Storage
TS3500 Tape Library uses a Fibre Channel interface (also called a port).*"

Why?  What is this "fibre channel interface" used for?   The 3494 use IP
to
communicate/manage the library and the drives inside the library used
fibre
plus an RS422 connection to the library manager.

On Sat, Jan 26, 2013 at 7:50 PM, Prather, Wanda
<Wanda.Prather AT icfi DOT com>wrote:

> Ah.  2-legged robots will work OK too.
>
> If there isn't a cartridge assignment map, when the operators (who are
> paying attention!) put the cartridges in the I/O door, they use the
library
> panel (or the web interface) to tell it  which logical lib to assign
that
> batch of cartridges to, then you run a TSM checkin as usual.
>
> The exact sequence varies depending on whether you have "virtual" I/O
> slots enabled with ALMS, but it's documented in the Operator's guide.
> So you should get the same resulting function as with your 3494.
>
> W
>
>
> -----Original Message-----
> From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf 
> Of
> Zoltan Forray
> Sent: Saturday, January 26, 2013 5:52 PM
> To: ADSM-L AT VM.MARIST DOT EDU
> Subject: Re: [ADSM-L] Tape library possible replacement - push/pull
>
> Operators paying attention when loading them ;-)
>
> Using category codes there are 2-library manager servers. Since only one
> LM is used for offsite, 99.9% of tapes bring checked in are handled by
it
> with bulk check-in.
>
> -------------
> Zoltan Forray
> TSM Software & Hardware Administrator
> Virginia Commonwealth University
> UCC/Office of Technology Services
> zforray AT vcu DOT edu - 804-828-4807
> Don't be a phishing victim - VCU and other reputable organizations will
> never use email to request that you reply with your password, social
> security number or confidential personal information. For more details
> visit http://infosecurity.vcu.edu/phishing.html
>  On Jan 26, 2013 5:18 PM, "Prather, Wanda" <Wanda.Prather AT icfi DOT com>
wrote:
>
> > >>>Carts get assigned to the logical libraries based on a volser range
> > filter in the library interface.
> >
> > No, that's not an absolute restriction, it's just a convenience.  It
> > allows the case where operators throw scratch tapes into the physical
> > I/O door and the library itself can shift them to the virtual I/O door
> > of the TSM library you want them checked in to, assuming the library
> > is partitioned into multiple logical libraries.
> >
> > How do you get the 3494 library "divided" now so that scratch tapes
> > get the category code of the appropriate library?
> > Or have you implemented 1 library with TSM library sharing, or what?
> >
> > 'Splain, and we'll help you figgur it out....
> >
> >
> > On Fri, Jan 25, 2013 at 10:01 PM, Prather, Wanda
> > <Wanda.Prather AT icfi DOT com
> > >wrote:
> >
> > > Yep, pretty much that simple.
> > >
> > > Check the tapes out of one library, check them into another.
> > > No more complicated than if you are going to a DR site that has a
> > > 3584 rather than a 3494.
> > > TSM doesn't care.
> > >
> > > There are some differences in the library management:
> > >
> > > If you are talking to the 3494 library interface via TCP/IP now,
> > > that changes.  (Some people use the TCP/IP interface, some use a
> > > serial
> > > cable.) TSM talks to the 3584 library via the atape drive over the
> > > fibre, it has its own device number/path.
> > >
> > > Thomas already mentioned that the 3584 can be partitioned into
> > > logical libraries.
> > > If you have multiple TSM servers or other apps using the 3494, you
> > > keep them separated now by 3494 category codes, those go away.
> > > You have the logical libraries now instead.  Carts get assigned to
> > > the logical libraries based on a volser range filter in the library
> > interface.
> > >
> > > W
> > >
> > >
> > > -----Original Message-----
> > > From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On
> > > Behalf Of Zoltan Forray
> > > Sent: Friday, January 25, 2013 2:08 PM
> > > To: ADSM-L AT VM.MARIST DOT EDU
> > > Subject: [ADSM-L] Tape library possible replacement - push/pull
> > >
> > > We are starting to examine the idea of replacing our aging 3494
> > > (installed
> > > 1995) due to difficulty in getting parts and having more frequent
> > > outages due to robot issues.
> > >
> > > Since we have 17-TS1130 drives, the natural transition would be to a
> > > TS3500/3584.
> > >
> > > If we go down this route, one issue might be the
> > > floorspace/placement, which might require a weekend
> eject-push-pull-reload.
> > >
> > > Never having dealt with any tape library other than the 3494, I am
> > > trying to collect as much info as I can on doing a swap-out.
> > >
> > > Is it as simple as defining the new library, moving the drives/paths
> > > to it,  changing the devclass to point to the new library, checkin
> > > everything (scratch/private)??  Am I missing anything?
> > >
> > > --
> > > *Zoltan Forray*
> > > TSM Software & Hardware Administrator Virginia Commonwealth
> > > University UCC/Office of Technology Services zforray AT vcu DOT edu -
> > > 804-828-4807 Don't be a phishing victim - VCU and other reputable
> > > organizations will never use email to request that you reply with
> > > your password, social security number or confidential personal
> > > information. For more details visit
> > > http://infosecurity.vcu.edu/phishing.html
> > >
> >
> >
> >
> > --
> > *Zoltan Forray*
> > TSM Software & Hardware Administrator
> > Virginia Commonwealth University
> > UCC/Office of Technology Services
> > zforray AT vcu DOT edu - 804-828-4807
> > Don't be a phishing victim - VCU and other reputable organizations
> > will never use email to request that you reply with your password,
> > social security number or confidential personal information. For more
> > details visit http://infosecurity.vcu.edu/phishing.html
> >
>



--
*Zoltan Forray*
TSM Software & Hardware Administrator
Virginia Commonwealth University
UCC/Office of Technology Services
zforray AT vcu DOT edu - 804-828-4807
Don't be a phishing victim - VCU and other reputable organizations will
never use email to request that you reply with your password, social
security number or confidential personal information. For more details
visit http://infosecurity.vcu.edu/phishing.html




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