Well rebooting the HSZ fixed the problem with the drives not responding.
But while recreating the device files the day before yesterday, I had
confused the device LUNS with the host LUNS. So, I now have access to
both drives. Attached is the replies from this group and one from DEC
support explaining how to create the device files with mknod.
Original message:
>Up until a power outage while on vacation last week I was happily using a
>TZ877 (DLT tape drive stacker) attached behind a HSZ40B, I actually has two
>drives but was only able to access one. Well the power went down and up
>again and since I was on vacation and there where so many other problems, no
>one checked my system till I came back from vacation. From what I can
>determine is that the system came up before the HSZ did and therefore did not
>see the drives. When I came back I was able to re-mount the disks which came
>up with a fsck or two, but NSR was unable to mount a tape. So, I tried
>rebooting the machine. I saw the drives at the >>> prompt, but when the
>machine came all the way up I still was not able to use the tape drive. I
>could even see the drives with the scu utility. So, thinking that maybe the
>drives had moved I built device files for them and still go nowhere. The
>message from NSR all along is "read error, device busy". Then, in case a
>messed up my math doing the device files I booted genvmunix and ran a
>doconfig. That failed to make and drives for the external tapes what so
>ever. Below is my log back to January, when I first had the tape drives
installed.
>
Replies from the group:
It sure sounds to me like your TZ877 (DLT tape drive stacker) took a hit
in
the power outage and is no longer working correctly.
The fact that the console firmware sees the device doesn't mean that the
device can actually be opened and accessed, just that the controller
will
respond to a suitable probe. The same goes for SCU.
If I had a service contract that covers the TZ877 DLT tape drive
stacker, I
would be calling to have it repaired.
Tom
Dr. Thomas P. Blinn, UNIX Software Group, Digital Equipment Corporation
110 Spit Brook Road, MS ZKO3-2/U20 Nashua, New Hampshire 03062-2698
Technology Partnership Engineering Phone: (603) 881-0646
Internet: tpb_at_zk3.dec.com Digital's Easynet: alpha::tpb
ACM Member: tpblinn_at_acm.org PC_at_Home: tom_at_felines.mv.net
Worry kills more people than work because more people worry than work.
Keep your stick on the ice. -- Steve Smith ("Red Green")
My favorite palindrome is: Satan, oscillate my metallic sonatas.
-- Phil Agre, pagre_at_ucsd.edu
Opinions expressed herein are my own, and do not necessarily represent
those of my employer or anyone else, living or dead, real or imagined.
We had the same kind of problems a couple of times. If you use dual
redundant HSZ40, make sure you switch both on at the same time and let
them
initialize properly before switching on the servers. A bounce of the
servers + HSZ solved our problems.
Get a decent UPS, that will also fix a LOT of problems.
Guy Dallaire
dallaire_at_total.net
"God only knows if god exists"
Use the "-o full" option of uerf to get the full listing of
the SCSI messages. Those may offer a clue.
Thanks for all the responses.
Here is DECs instruction on building the device files:
> [DEC OSF/1] Adding a SCSI tape device to a HSZ controller
>
> OP/SYS: Digital Unix, Version 3.X
>
> SOURCE: Digital Equipment Corporation
>
> Question:
>
> You are trying to add a non 0 lun tape device to a raid/hsz controller
> and it does not work with MAKEDEV to create devices. How can you add it.
>
> ANSWER:
>
> Adding a SCSI tape device to a Raid controller with a lun other than 0
> can be quite complicated. When adding to a standard controller, one uses
> the 'MAKEDEV' command along with the tape identifier. When adding to a
> Raid controller, you must use a series of formulas plus use the make
> node command, (mknod), to add all the drivers manually. The following
> steps are prepared to illustrate the proper procedure for installing
> a tape device. Also there will be excerpts from the 'man(7) SCSI' man-
> ual pages where this procedure can be found. This article is intended
> for clarity.
>
> For the sake of a naming convention, lets assume we are dealing with the
> following:
>
> The tape unit is identified as MKB107 which indicates that it is target
> id 1, bus 1, lun 7. This also points out that the device then would be
> tz9 using the convention :
>
> Bus 0= tz8
> Bus 1= tz9
> Bus 2= tz10 etc........
>
> If you are using a lun of 0, then you could use the standard creation as
> described in the first paragraph using the MAKEDEV command, but in this
> case we are using lun 7 which means we have to create our own drivers
> with mknod.
>
> The following diagram describes the minor numbers for SCSI tape devices:
>
> -----------------------------------------------------------
> Bits: | 19 14 | 13 10 | 9 6 | 5 1 | 0 |
> -----------------------------------------------------------
> | Bus no. | Target ID | LUN | Density | No rewind |
> -----------------------------------------------------------
>
> The calculation is then as follows:
>
> (lun x 64)+(target ID x 1024)+(bus no. x 16384)+(density x 2)+no_rewind
>
> To add our tape, we do the following calculation:
>
> Density Lun=7 Target=1 Bus=1 Density r/w
> -------------------------------------------------------
> low: (7x64) + (1x1024) + (1x16384) + (0x2) + 0 = 17856
> high: (7x64) + (1x1024) + (1x16384) + (1x2) + 0 = 17858
> med: (7x64) + (1x1024) + (1x16384) + (2x2) + 0 = 17860
> aux: (7x64) + (1x1024) + (1x16384) + (3x2) + 0 = 17862
>
> Notice the increments of 2 forced by Density:
>
> Perform the calculations for the no rewind device files:
>
> Density
> low: (7x64) + (1x1024) + (1x16384) + (0x2) + 1 = 17857
> high: (7x64) + (1x1024) + (1x16384) + (1x2) + 1 = 17859
> med: (7x64) + (1x1024) + (1x16384) + (2x2) + 1 = 17861
> aux: (7x64) + (1x1024) + (1x16384) + (3x2) + 1 = 17863
>
> Now create the rewind devices:
>
> # mknod /dev/rmt0l c 9 17856
> # mknod /dev/rmt0h c 9 17858
> # mknod /dev/rmt0m c 9 17860
> # mknod /dev/rmt0a c 9 17862
>
> Now create the no-rewind devices:
>
> # mknod /dev/rmt0l c 9 17857
> # mknod /dev/rmt0h c 9 17859
> # mknod /dev/rmt0m c 9 17861
> # mknod /dev/rmt0a c 9 17863
>
> Now , all devices are created but you must add the divers to the config
> file and rebuild the kernel. In this file to add our tape added:
>
> device tape tz9 at scsi1 drive72
> device tape tz9 at scsi1 drive73
> device tape tz9 at scsi1 drive74
> device tape tz9 at scsi1 drive75
> device tape tz9 at scsi1 drive76
> device tape tz9 at scsi1 drive77
> device tape tz9 at scsi1 drive78
> device tape tz9 at scsi1 drive79
>
> This is all that is needed to get a tape installed on a raid controller.
--
[ Alexander Williams {thantos_at_alf.dec.com/zander_at_photobooks.com} ]
[ Alexandrvs Vrai, Prefect 8,000,000th Experimental Strike Legion ]
[ BELLATORES INQVITI --- Restless Warriors ]
====================================================================
---
Ronald D. Muller
Information Systems Professional III
Network Services Section
King County
Information and Telecommunications Services Division
Department of Information and Administrative Services
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Seattle, WA 98104
(206) 869-3487 Fax 689-3145 Pager 969-1677
Internet: ronald.muller_at_metrokc.gov
Received on Wed Mar 26 1997 - 21:20:05 NZST