Info-3b2 Digest, Number 63

Info-3b2 Mailer info-3b2 at lamc.UUCP
Wed Mar 1 04:49:27 AEST 1989


 
                           Info-3b2 Digest, Number 63
 
                          Tuesday, February 28th 1989
 
Today's Topics:
 
                     Re: 3b2 Questions - Answers Appreciated
                                   u3b.sources
                             UUCP bug not in SVR3.0.
                     Re: 3b2 Questions - Answers Appreciated
----------------------------------------------------------------------
 
From: rich at jolnet.Orpk.IL.US (Rich Andrews)
Subject: Re: 3b2 Questions - Answers Appreciated
Date: Sat, 25 Feb 89 11:17:47 CST

> 
> Forwarded message:
> 
> Subject: 3b2 Questions - Answers Appreciated
> Date: 23 Feb 89 15:30:58 GMT
> Organization: Cornell Theory Center, Cornell University, Ithaca NY
> 
> 	We have several 3b2/310's running System 5 version 3.1
> 	with WinTCP 1.1, net card, 30meg drive, floppy and a 
> 	4serial/1parallel card. All systems were originally
> 	3b2/300's that were upgraded by ATT technicians at our
> 	site.  We have a list of questions that we can't, as yet*,
> 	find answers to, so if anyone can help in all or in part,
> 	please respond by reply, e-mail direct to me or phone,
> 	which ever is easiest for you.
> 
> 	* We have asked our resident ATT expert, ATT sales reps
> 	  and perused the manuals rather thoroughly (we think)
> 	  trying to answer the questions posed.
> 
> 	Questions:
> 
> 	1; Is there a way to make a bootable floppy system
> 	   so we can try to salvage systems that are having a problem
> 	   without doing the 'Essential utilities, partial restore'
> 	   route? Essentially a kernal with mount, fsck, makedev
> 	   etc so we can boot, fsck the hard drive and mount it.

               Running a Standalone Shell on a 3B2

                        Stephen J. Friedl
                         V-Systems, Inc.

                         April 25, 1988

          NG:  the   procedures   described   here
          require  substantial  knowledge  of  UNIX and
          entail a significant risk of causing loss  of
          data.  The obvious disclaimers apply here, so
          use at your own risk.  Please be careful.

Introduction

     AT&T has developed some very simple, automated procedures
for doing just about everything required to administer a 3B2
computer.  They do this with the help of detailed, step-by-step
manuals and some pretty decent sysadm menu software.  The
difficulty is that there are some things that just can't be done
easily via the menus; fixing a dead machine is one of them.

     This document is an introduction to operating your 3B from
a standalone /unix.  Even with inoperable hard drives, it is
possible to insert the boot floppy (Essential Utilities Disk 1),
say some magic words, and receive a # prompt.  At this point you
can do major surgery on the failing machine, often recovering a
drive previously thought to be lost.

     Our style is informal and we'll use lots of examples to
illustrate the points at hand.  We have been using standalone
shells for quite some time and have learned a great deal; we hope
to pass this information on to you.  Please read this document
carefully before trying the methods described here, and if
possible have a wizard around when giving it a go.  This can be
dangerous business: as has been said before, it is a time where
experience and informed courage count for much.

     All of these notes were derived by looking at disks, picking
apart little programs, and generally by running into problems
we were bound and determined to solve.  We are not a source code
licensee, and as such, we have made certain assumptions about
some of the pieces of this puzzle, those assumptions possibly
having limited correspondence with reality.  Those with more
enlightenment are encouraged to fill us in on changes.

                              - 1 -

Conventions

     Throughout this document, sample usage sessions will be
shown indented, with user input in bold.  To make it easier
to distinguish between a multiuser UNIX shell and a standalone
one, we will show multiuser UNIX's root prompt as ## and the
standalone prompt as #.

>>> Back up your boot disks b->

     This cannot be emphasized enough.  Your boot floppies are
the key to your machine, and without them the machine is down.
Early in our experiences with standalone shells, our primary boot
floppies became corrupted early on a Saturday, and we had to wait
until Monday morning for AT&T to provide us a spare; it was as
embarrassing as it was frustrating.  It is mandatory that you
have at least three copies of your boot disk before you begin
these procedures.  While it is easy to have too few backups, it
is hardly possible to have too many.

     The most efficient method for copying an entire floppy is
with the dd(1) command.  First, read a copy of the entire floppy
into a single file under /tmp.  Be sure that room for the entire
filesystem -- 1435 blocks -- is available on the hard drive.

          ## dd if=/dev/rdiskette of=/tmp/disk.copy bs=9b
          158+0 records in
          158+0 records out

     This reads from the boot disk into the file /tmp/disk.copy,
using the floppy's optimal blocksize.  The command will take
somewhat over two minutes, and the input/output statistics shown
above are normal.  Now, insert a formatted floppy into the drive
and do:

          ## dd of=/dev/rdiskette if=/tmp/disk.copy bs=9b
          158+0 records in
          158+0 records out

     Notice that the `if' and `of' options are the only changes,
signifying the reversal of copying direction.  This second
command can be used repeatedly to make as many copies of the disk
as desired.  Do remember to remove the /tmp/disk.copy file after
all copies have been made.

Why do you want a standalone /unix?

     The most compelling reason for a standalone shell is when
the primary drive has gone down and must be recovered.  While
working from a standalone /unix is slow and tedious, it can often
save an entire hard disk with minimal data loss.

                              - 2 -

     Case in point: a friend called in a panic.  He had done
a dd(1) onto his hard drive improperly and had overwritten the
drive's partition tables, rendering it unbootable.  He was able
to boot a standalone /unix from a floppy, manually initialize the
partition tables, and get his drive back with not a byte lost.
All it cost was a cross-country phone call and a half an hour of
time (plus a nice dinner next time he's in town).

     We have also used this standalone shell to repair a corrupt
/etc/inittab, to fix /etc/passwd, to restore a /bin/login
that had been removed, and to install new bootstraps on the
hard drive.  With a standalone boot disk in hand, a host of
possibilities presents itself.

What is on your boot disk?

     Before booting this floppy, take some time to explore
its contents, as the disk has a filesystem on it that can be
mounted and perused.  To do this, insert a copy of the Essential
Utilities Floppy 1 (from now on, "the boot floppy") into the
drive with a write-protect tab.  Now,

          ## mount /dev/dsk/c0d0s5 /install -r

     Because this disk has a boot partition that resides on the
first cylinder, the more commonly used /dev/diskette (slice 6) is
replaced by /dev/dsk/c0d0s5 (slice 5).  The `-r' flag asks that
the filesystem be mounted readonly.

     The /install directory may now be visited like any other,
but remember that a floppy-based filesystem responds much slower
than one based on the hard drive.  With this in mind, it is
helpful to insure that the current directory appears at the tail
end of the shell's search $PATH when exploring a floppy.

     Because boot floppies vary from release to release, it would
be most helpful to simply get a listing of the contents of your
particular boot floppy.  Do this by:

          ## cd /install
          ## ls -lRFab | pr | lp

     This sends a formatted listing of the entire disk to the
printer; keep it handy.

     The next step is to examine the particular installation
procedure used by this version of the boot floppy.  Look in
/install/etc/inittab for the name of the program that does the
work, and on our disks (SVR2.0.4) the file is /inst/etc/instf
(which is found in /install/inst/etc/instf if the floppy is
mounted on the hard drive).  This installation script is fairly
verbose, and tracking down just what it is doing should be

                              - 3 -

straightforward and enlightening.

     Once finished, the floppy must be unmounted:

          ## cd /
          ## umount /dev/dsk/c0d0s5

     Never remove a mounted floppy filesystem without first
unmounting it, especially a boot disk.  Doing this may leave the
filesystems's status flag in an "active" state and prevent the
boostrap from recognizing it.  The umount operation insures that
the disk is properly updated before it is closed.  When the green
drive light goes off, remove the floppy and return it to its
proper home.

"Open Sesame"

     To give standalone a try, first shut the machine down to
firmware mode.  From multiuser UNIX, warn the users that the
machine will be unavailable, and run the following from the
system console:

          ## cd /
          ## /etc/shutdown -i5

     This brings the machine into init state 5, which is firmware
mode.  The shutdown program will verify your intentions, send
a notification to all logged-on users, and bring the machine to
firmware mode in one minute.

     Assuming the machine is now in firmware mode, put a copy
of the boot disk into the drive.  Note that some versions of the
operating system (Sys V Release 2, at least) require that the
boot floppy be write-enabled (i.e., no write-protect tab); it
is this requirement that mandates multiple backups of the boot
floppy.  UNIX will be updating the disk while it runs -- the
superblock, access times, etc. -- and if the machine crashes at
the wrong time it simply will not boot again without an fsck.  Be
careful.

     Type in your firmware password and boot /unix from the
floppy drive (Option 0, named `FD5') instead of the hard drive
(Option 1, named `HD30' or `HD72').  It can take several minutes
for UNIX to boot, but when it does, the familiar menu will be
displayed:

               1) Full Restore
               2) Partial Restore
               3) Dual-Disk Upgrade
               4) Release Upgrade

                              - 4 -

               Selection? [1, 2, 3, 4, quit, help]

     At this point, type the phrase

                           magic mode

     The system recognizes this special option and responds:

          Poof!

          Selection? [1, 2, 3, 4, quit, help, shell, copy]

     Notice the new options?  Now type shell, then RETURN, and
you will be greeted with the familiar # prompt.  You are now
running a standalone shell on the floppy.

     A few reminders here: a floppy filesystem is not able to
hold much data, and many common utilities are unavailable.  When
dealing with the standalone shell, one must learn alternatives
to these utilities.  For example, echo * can replace ls(1), and
cat > file can serve as a poor replacement to ed(1).  One must
become remarkably resourceful when working in an environment as
restricted as this.  We will see later how we can enhance this
confined environment with additional tools.

Standalone devices

     The floppy's /dev directory contains a host of entries,
some of them referring to partitions on the hard drive.  While a
particular partition may have several names, we generally use the
following devices to refer to the hard disk:

          Partition        What it is (on the hard disk)
          -----------      -----------------------------
          /dev/idsk00      / filesystem
          /dev/idsk01      swap area
          /dev/idsk02      /usr filesystem
          /dev/idsk06      the entire disk
          /dev/idsk07      boot partition
          /dev/idsk08      optional filesytem (/u or /usr2)

     These also have names of the form /dev/dsk/c1d0s0, but
we prefer using the shorter names because they tend to be
less confusing.  In addition, each block device mentioned has
a corresponding character (raw) device entry of the form
/dev/ridsk00 (note initial `r').  Generally, we use the block
devices where a choice exists.

     The cartridge tape drive is not available in standalone mode
because the floppy is not large enough to hold /unix with the CTC
drivers.  Because of this, there are no device entries in /dev
that correspond to any tape drives.  There are intermediate

                              - 5 -

solutions to this problem but they are beyond the scope of this
document and not usually necessary.

Mounting the hard drive onto the floppy

     To gain access to the primary hard drive, partitions of
interest are mounted onto directories on the floppy.  The device
names are selected from the table in the previous section.

     Before mounting a partition, we recommend running the
filesystem check fsck(1m) first.  The mount command will fail
if the the superblock is not in order -- this is often the case
after a crash.  In addition, it gives a convenient verification
of the device status and the the filesystem's name and volume.

          # /etc/fsck /dev/idsk00

     While some errors are to be expected while checking the
root partition, a total failure is a very serious error.  Our
experience defines "total failure" as an indication by fsck
that it cannot find any possible traces of a filesystem.  In
particular, "CAN NOT READ: BLK 1" is one of the more ominous
messages we have seen.  

     It indicates either (A) the partition tables have been
destroyed, (B) there are hardware problems with the drive, or
(C) the boot floppy is bad.  If the same message is printed from
different boot floppies, and it remains after checking the drive
cables, call AT&T for help.  The message "hard disk: Bad sanity
word in VTOC on drive 0" is a virtual guarantee of corrupted
partition tables, and the procedures for their repair are
dangerous, intricate and beyond the scope of this manual; call
AT&T for help.

     Once fsck grants the filesystem a clean bill of health, it
is ready to be mounted.  Rather than take up space for a handful
of common commands, AT&T has rolled several of them into one:
fsys.  It is undocumented and appears to only be used on the boot
floppy.

     Fsys takes a handful of options, not all of which are
interesting to us in standalone mode.  Used in the install
scripts for a handful of filesystem-related duties, we will use
it simply as a replacement for mount(1m) and umount(1m).  To
mount the hard disk's root filesystem onto the floppy's /install
directory, do:

          # fsys -m /install /dev/idsk00

     Fsys will complain on an error, and this brings us to a
serious bug in this program: if either the mount directory or
the partition's device name are invalid for any reason, the error
message will always point to the partition device name.  This can

                              - 6 -

be, to put it lightly, "misleading".

     Anecdote: we were running a standalone boot on a machine
whose main drive had just come back from the shop.  We were
being very cautious, having already had an exceedingly unpleasant
experience with hardware failure on this customer's machine.
When trying to mount the hard drive onto the floppy, we did:

          # fsys -m /mnt /dev/idsk00
          fsys: /dev/idsk00: no such file or directory

     A hard-disk based UNIX on a 3B2 usually has a /mnt directory
used as a floppy mount point, but the floppy UNIX does not have
one (/install should be used instead).  At this point, however,
we were not aware of the nature of our mistake.

     Since the device name /dev/idsk00 was indeed found in /dev,
the above error message led us to believe that the drivers could
not find the hardware and the drive itself was in very bad shape
(again).  Ten panicky minutes later we realized that the error
message was wrong, and mounting onto /install instead of /mnt
worked as expected.

     With the hard drive's root filesystem mounted on /install,
it is now fully part of the standard directory tree.  While
the floppy has no editor or many of the helpful tools, the root
partition does, and these can be exploited.  When beginning an
extended standalone session on the primary drive, we have found
it helpful to extend the shell's search path:

          # PATH=/install/bin:/install/etc:$PATH ; export PATH

     Now the familiar ls, ed, (but not vi) and many other
commands are available.  Since they will be loaded from the hard
drive, execution is much faster.

     As an example, assume that the root password has been
forgotten and the machine is basically closed.  The solution
suggested by AT&T's documentation (in the System Administration
Utilities Guide) is to do a partial restore.  The difficulty with
this approach is that many important system files -- /etc/passwd,
/etc/inittab, /etc/gettydefs, and others -- are overwritten in
the process.  Even with a full backup, this can be an unpleasant
undertaking.

     An alternate approach will use the standalone shell.  The
general strategy is to mount the hard drive, edit the password
file, and boot multiuser UNIX.  The full procedure is:

          (boot standalone /unix)
          # fsck /dev/idsk00
          # fsys -m /install /dev/idsk00
          # /install/bin/ed /install/etc/passwd
          (edit the file in the standard way)

                              - 7 -

          w
          q
          # fsys -u /dev/idsk00

     At this point, the root drive is now unmounted and the
system may be rebooted.  We are not sure of the best way to do
this, so we usually sync the disk and return to firmware with:

          # sync
          # /etc/uadmin 2 2

     Uadmin(1m) is documented in the manual (you must also
refer to the uadmin(2) manual page) -- the above does a normal
return to the monitor (i.e., firmware).  WARNING: uadmin(1m)
is available from full UNIX as well but is very dangerous.  Use
it with extreme caution and only if you really know what uadmin
does.

Making a standalone boot disk

          ================== WARNING ==================
          Only do this on backup copies of  the  disks,
          NEVER to the main Essential Utilities Disk.
          ================== WARNING ==================

     The Essential Utilities Disk 1 contains many files needed
by the automatic restore/upgrade procedures, but for standalone
work, many are not needed.  After working with these disk for
some time, we were able to narrow down what is helpful to have
on the disk and what is not.  The following procedure (run from
multiuser mode, signified by the ## prompt) will convert an
Essential Utilities disk to a standalone boot disk.

          (from hard disk UNIX)
          ## fsck /dev/dsk/c0d0s5
          ## mount /dev/dsk/c0d0s5 /install
          ## cd /install/inst/bin
          ## mv fsys pdinfo swap ttyset ../../bin
          ## cd /install
          ## /bin/rm -rf inst
          ## cp /bin/ed /install/bin
          ## cp /etc/fsdb /install/etc
          ## cat > /install/inittab
          is:s:initdefault:
          sh:s:respawn:/bin/sh < /dev/console > /dev/console 2>&1
          ^D
          ## cd /
          ## umount /dev/dsk/c0d0s5

                              - 8 -

     While there may be other files on this floppy that are not
needed, we have operated on the principle of least customization.
It has been our experience that keeping the procedure simple
allows it to be done on-the-fly (say, at a customer site) and
minimizes the exploration required when a new operating system
disk is released.

     In addition, it is not wise to pack the disk too tightly.
The editor requires adequate space under /tmp, so an almost-full
disk precludes editing all but the smallest files; this applies
whether the file being edited resides on the hard drive or the
floppy.

     Once this is done, the new disk will come up in standalone
mode without the need for magic mode.  In addition ed(1) and
fsdb(1m) are available.  The other tools mentioned (pdinfo, swap,
ttyset) are helpful but not required by the basic procedures.

     Over time, the resourcefull standalone booter will likely
develop tools that help repair damaged UNIX systems; these can
often go onto these boot floppies.  Remember to strip(1) files
before putting them onto the disk, because the symbol table is
useless and wastes precious space.

     It has been our experience that any version (SVR2, SVR3)
of boot disk can be used with any version of hard disk UNIX
without difficulty for doing simple operations such a performing
filesystem checks or editing /etc/passwd.  For more complex
operations, such as repartitioning the hard drive or restoring
the bootstraps, higher version compatibility is required.

Security Considerations

     It should be apparent that knowledge of these standalone
methods is tremendously powerful.  In addition to being able to
rescue a foundering machine, an unrestricted path to root has
been provided as well.  While all the standard rules about
physical security of the computer apply here, an additional step
may be taken to thwart a would-be interloper.

     The responsible system administrator of a machine in a
hostile environment will generally change the computer's firmware
password.  This magic word is required before the monitor on
the 3B2 motherboard will boot from a floppy, and lack of this
password prevents a malicious user from simply pulling the power
plug to enter firmware mode.

     In addition to changing the firmware password, the floppy
key floppy should itself be secured.  When the computer is
restarted with this disk in the drive, it will clear the
non-volatile RAM (NVRAM) and restore the default parameters.
Because the firmware password is included in these "default

                              - 9 -

parameters", this disk should be kept out of non-trusted hands.

Conclusion

     For those comfortable with its use, a standalone shell can
be a time/lifesaver and can obviate the need for many partial
and full restores.  Those wishing to use the methods described
here are encouraged to explore them prior to their need.  The
experience gained by a relaxed hour or two of investigation will
be more than repaid when the machine crashes and the procedures
are no longer "optional."

     In addition, the layout of a standard boot disk varies
somewhat from release to release.  While the general approach to
a standalone boot remains similar, some preliminary examination
may forestall unpleasant surprises when the machine conditions
are less hospitable.

     We solicit bug reports, comments, and suggestions on this
document.  Please direct them to:

          V-Systems, Inc.
          39 Brookhollow Drive
          Santa Ana, CA  92705-5440
          (714) 545-6442
          Attn: Steve Friedl

          Internet:  friedl at vsi.com
          AT&T Mail: attmail!vsi!friedl
          Usenet:    {backbones}!vsi.com!friedl

                              - 10 -

#------------------------- cut here ------------------------------------

> 
> 	2; "WARNING: niwrite: ni_send failed - ret code=8"
> 	   We keep getting this network error repeated about every 
> 	   thirty seconds that we can't track down and
> 	   after swapping several boards it is still there so I see it
> 	   as a software or protocol problem. We have one system
> 	   directly on the net (h4000 xcvr---->3b2) that doesn't
> 	   ever show it but any system on our delnii does;
> 	   (h4000------->DELNII------>3b2) - other systems on the DELNII
> 	   show no problems (uVaxII, Kinetics FastPath)
> 	   Network performance and connections don't seem to be affected.
> 	   Routed and tftpd are turned off. It is vexing.
  
> 	   What are the proper diagnostics to run on the net interface
> 	   and where is the info on them?
sorry i cannot help you with that question....  
> 	3; Hard drive questions;
> 		a; Do the 3B2's use a standard configuration hard drive?
> 		   ie: What will fit and how much is it?

The thing you need to order so that you can low level format your disks is:

	"AT&T 3B2 Computer Maintenance Reference Manual"

	Select Code: 305-395 ..... Issue 2

You should be able to order it from wherever you got your existing
system and doc's.  If not try:

	1-800-247-1212 (USA)	1-201-953-7554	(elsewhere)

This manual gives pretty good service procedures for the 3b2 line
300's through 600's. Also for SCSI and XM stuff.
You will also get comcodes for most of the replaceable parts.
The DEVTOOLS diskette is now known as the idtools (lower case) diskette
and is included in the back of the manual.
I think the cose is either $50 or $100.

> 		b; What does it take to mount a second hard drive either
> 		   in the 3b2 chassis or outside. We have a couple of
> 		   spare 30meg drives that we would like to put in
> 		   place of the floppies on a couple of systems. Can that
> 		   be done? - It looks like the cables to the hard drive
> 		   port in the back could just be pulled off and connected
> 		   to another drive, except for the little 2 wire cable
> 		   from the port to the internal drive. Also what drive
> 		   selects to use?
> 
> 		c; Is there a place that rebuilds the drives at an effective
> 		   cost?
> 
> 	4; Maintenence Questions;
> 		a; Does ATT have a mail in program analogous to DEC's
> 		   DECMAILER program? 

not that I know of...they do have a carry in service though althought you can order
parts via mail.....call 1800-222-part
  
> 		b; Is there an independent repair facility for 3b2 
> 		   board level repairs?
if there is do not trust them...... 
> 		c; Are there any hardware manuals available for the 3b2/310?
> 	
> 	5; Software questions;
> 		a; Is there an 'rdump' around that will allow you to dump
> 		   to a remote (Ultrix) system.
> 
> 		b; Is NFS available?
try mailing to postmaster at laidbak and see if you can get an answer to that 
> 		c; Is there a csh or csh like environment available?
> 		   
  try ksh.....it really is nice.
> 
> -- 
>      Hurf Sheldon			 Network: hurf at ionvax.tn.cornell.edu
>      Lab of Plasma Studies		  Bitnet: hurf at CRNLION
>      369 Upson Hall, Cornell University, Ithaca, N.Y. 14853  ph:607 255 7267
>      I sold my Elan, got a job in science; Now, no one takes me seriously.
> 
> --
> 

rich andrews 
rich at jolnet.orpk.il.us
(yes this is a 3b2/400)

------------------------------
 
Date: Sun, 26 Feb 89 07:18:49 est
From: len at netsys.COM (Len Rose)
Subject: u3b.sources

 Greetings..

  I hope to create u3b.sources soon,and would like to ask everyone to
  submit things that have been ported to the 3B2 series of systems..

  Things I envision posting would be a recent release of sendmail,TeX,
  and other hard to port software. I have contacted someone about TeX,
  but haven't found anyone who has hacked sendmail (a recent version). 

  I have tried to reach the people who were in the process of porting gcc
  to the machine, but haven't received any replies.

  At this point, any source,diffs,scripts,etc will be welcome. I don't
  think the u3b source news group would need to be moderated. We are all 
  professionals within this group.

  If you are not receiving the u3b distribution, contact your news admin
  If he or she cannot help you, and you need a feed , contact me.
  
  I am in the process of conducting a propigation analysis with u3b,
  and will be posting the connectivity data in u3b.config as soon as
  the sys files stop coming in. So far, it looks great. As I expected
  it's being extremely well distributed within AT&T. <smile>

  Len
 

-- 
len at netsys.com
{ames,att,rutgers}!netsys!len

------------------------------
 
From: uunet!mcvax!acsdk!tonny
Date: Sun, 26 Feb 89 09:06:31 +0100
Subject: UUCP bug not in SVR3.0.

> Situation: When dialing other sites that have multiple Systems
>            line entries,with different baud rates,uucico fails
>            on the second entry because it doesn't set the baud
>            rate correctly in the second Systems entry.
>
>  I.E. Anysite Any ACU 2400 etc etc etc
>       Anysite Any ACU 1200 etc etc etc <-- fails to set line at 1200

We are using UNIX System V Release 3.0 on a AT&T 3B2/300 and uucico
works fine here.  So maybe an upgrade will do ?

Tonny Andersen / Advanced Computer Software / Denmark
mcvax!dkuug!acsdk!tonny

------------------------------
 
Subject: Re: 3b2 Questions - Answers Appreciated
Date: Sun, 26 Feb 89 17:30:46 GMT
From: Graham Glen (Technical Manager) <qukmips!graham>

Here I go in feet first as always  :-)

> 
> 	Questions:
> 
> 	1; Is there a way to make a bootable floppy system
> 	   so we can try to salvage systems that are having a problem
> 	   without doing the 'Essential utilities, partial restore'
> 	   route? Essentially a kernal with mount, fsck, makedev
> 	   etc so we can boot, fsck the hard drive and mount it.
> 

Yup. Start off by copying the "Essential Utilities" disk 1. This is a
bootable disk with almost everything you need on it. If you boot of the
"Essential Utilities" disk you get 4 options (from memory), instead of
entering 1-4 if you enter "Magic Mode" (it may be "magic mode" it's a while
since I've done this), you will be put into a shell. However, the shell has
almost nothing set in its environment. Some things go under different names
on the Essential Utilities disk, "mount" for example is "fsys". A good
precaution is to mount an Essential Utilities (EU) disk on a running
machine (device /dev/dsk/c0d0s5) and hunt through for all the executables.

I modified a copy of the EU disk so that instead of trying to give you the
menu, it would fsck the root partition on the hard disk, mount it and then
copy all of the really important files which might be corrupt to backup
names and then overwrite them. So things like /etc/passwd & /etc/inittab
would all be replaced by minimal entries to get the system back up. The
copied EU disk would then unmount the hard disk and call /etc/uadmin to
re-boot the machine.

If it's only your kernel that is trashed, from firmware you could try
re-booting from /etc/system, or if that fails you can boot from
/boot/KERNEL.

> 	2; "WARNING: niwrite: ni_send failed - ret code=8"
> 	   We keep getting this network error repeated about every 
> 	   thirty seconds that we can't track down and
> 	   after swapping several boards it is still there so I see it
> 	   as a software or protocol problem. We have one system
> 	   directly on the net (h4000 xcvr---->3b2) that doesn't
> 	   ever show it but any system on our delnii does;
> 	   (h4000------->DELNII------>3b2) - other systems on the DELNII
> 	   show no problems (uVaxII, Kinetics FastPath)
> 	   Network performance and connections don't seem to be affected.
> 	   Routed and tftpd are turned off. It is vexing.
> 
> 	   What are the proper diagnostics to run on the net interface
> 	   and where is the info on them?

As a guess, might you have a damaged or somehow below spec transceiver drop
cable? 

To run diagnostics on the NI card, go to firmware and boot dgmon. The
"Systems Administrators" manuals should give you enough to get started on
this one, but not much more.

Of course, the diagnostics are probably written so they never test for any
REAL error conditions. :-)

> 
> 	3; Hard drive questions;
> 		a; Do the 3B2's use a standard configuration hard drive?
> 		   ie: What will fit and how much is it?

You should be safe with fitting any ST506 drive into a 300,310 or 400. I
don't know what sort of prices AT&T charge over there, but over here things
like disk upgrades (supplied by Olivetti) are frighteningly expensive. So
much so that it's cheaper to buy and fit the drives yourself, and if every
drive went bang and you had to replace it with a new one you'd still end up
paying less.

I can't help with any of your other questions I'm afraid, but I'm sure
somebody else out there will be able to.

Graham

--
Graham Glen			      | Voice +44 1 371 5755
Quadratron Systems (UK) Ltd.	      |       +44 836 380006 (mobile)
--------------------------------------+----------------------------------------
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