PDP-10.its/troubleshooting.md

Troubleshooting guide

This guide will help you sort out the most common issues of running ITS on the PiDP-10

INQUIR not saving changes

Thanks to eswenson for the intial steps here

In order for INQUIR entries to stick, you must have COMSAT running.

If you run PEEK, you should see two COMSAT jobs. One has the JNAME IV and the other JOB.nn. If these jobs are not present, then COMSAT may have started and died or not started at all

*:peek
KA ITS 1651  Peek 631   8/14/2024 09:59:35  Up time = 5:05
Memory: Free=457   Runnable Total=11 Out=3     Users: High=13 Runnable=0
Index Uname Jname Sname     Status   TTY    Core Out %Time    Time PIs
  0 SYS    SYS    SYS        HANG    ?        71   0   0%          1
  1 CORE   JOB    CORE       UUO     ?         0   0   0%
  2 MIKEK  HACTRN MIKEK      HANG    >        30   9   0%
 12  MIKEK  PEEK   MIKEK     +TTYBO  T52 C    11   2   0%
  3 .BATCH BATCHN .BATCH     SLEEP   ?       126  23   0%
  4 TARAKA CNAVRL CNAVRL     10!0    ? DSN    29   0   0%          .VALUE
  5 GUNNER GUNNER GUNNER    _SLEEP   ?        11   3   0%
  6 TARAKA PAPSAV PAPSAV     HANG    ?         1   0   0%
  7 TARAKA NAMDRG NAMDRG     HANG    ?        29   0   0%
 10 PFTHMG DRAGON PFTHMG     HANG    ?         6   0   0%
 11 TARAKA JOB.07 SYS        HANG    ?         3   0   0%
Fair Share 99%     Totals:                   317       0%          1
Logout time =         Lost 0%  Idle 98%  Null time = 5:07

As you can see above none of the COMSAT process is running.

There are several reasons why COMSAT may die upon startup The most common are: Lets start going through those one by one:

Network parameters for COMSAT are not correct.

When you bring up KA ITS, you'll see a message on the operator console like this:

 LOGIN  TARAKA 0 12:09:11 TOP LEVEL INTERRUPT 200 DETACHED JOB # 4, USR:COMSAT IV     12:09:12

This means that COMSAT has crashed.

If you look at the IP address that COMSAT is configured with:

comsat$j
$l .mail.;comsat launch
bughst/'NEW$:   SHOWQ+50,,PAT+6   =30052000544

you'll note that that octal address is: 192.168.1.100

If you look at the value that ITS has for the machine's IP address:

sys$j!
*impus3=1200600006

You'll see that that that octal address is: 10.3.0.6

And if you look at the host table (SYSHST;H3TEXT >), you'll find an entry like this:

HOST : CHAOS 177002, 192.168.1.100 : DB-ITS.EXAMPLE.COM, DB : PDP-10 : ITS : :

(And there is no HOST entry for a machine with the name KA).

The easiest fix is to:

1. fix the host table
2. fix COMSAT's variables
3. generate COMSAT's database files
4. fix COMSAT's mailing lists file
5. restart COMSAT

To fix the host table, change the line:

HOST : CHAOS 177002, 192.168.1.100 : DB-ITS.EXAMPLE.COM, DB : PDP-10 : ITS : :

to

HOST : CHAOS 177002, 10.3.0.6 : KA : PDP-10 : ITS : :

Save the updated SYSHST;H3TEXT > and then compile the host table:

:SYSHST;H3MAKE

Make sure that there were no errors (look for a H3ERR file) and make sure that there exists a file SYSBIN;HOSTS3 NNNNNN where NNNNNN matches the FN2 of the SYSHST;H3TEXT NNNNNN you just created.

Now your host table matches your ITS IP address.

Next, you need to fix COMSAT.

To do that, create a job for COMSAT:

comsat$j

Then load in the compiled (but not dumped) binary for COMSAT

$l .mail.;comsat bin

And now set various variables:

BUGHST/1200600006
DEBUG/0
xvers/0

And then purify the binary:

purify$g

and when DDT prints out:

:PDUMP DSK:.MAIL.;COMSAT LAUNCH

Type an <enter> to confirm.

Now, you have an correct .MAIL.;COMSAT LAUNCH executable.  This will be launched by TARAKA on startup, or by :MAIL when invoked if COMSAT isn't running.

However, before you do this, you need to make sure that COMSAT's database files are created.

To do that, do this:

comsat$j
$l .mail.;comsat launch
debug/-1
mfinit$g

You should see a message like:

:$ File Directory Initialization successfully completed...
Proceeding will launch Comsat. $
*

Don't proceed the COMSAT job, because it will be run as your UNAME rather than COMSAT's.  Simply kill the COMSAT job:

:kill

Now, there is one last step.  The file .MAIL.;NAMES > has entries for DB (ITS) rather than KA.  It needs updating.

In emacs, open up .mail.;names > and do a query replace of all instances of DB with KA.

To do that, enter the Query Replace command:

<escape>%

The echo area should display:

MM Query Replace$

Type in DB<escape>KA<escape><escape>

Your cursor will be positioned at the first instance of the string DB.

Type in

!

Yes, just the exclamation point character.  This will replace all instances of DB with KA.

Save the file. (<control>x<control>s) and return to DDT (<control>x<control>c).

Now, you are ready to launch COMSAT.

But first, make sure there is no (dead) comsat running, but running peek$k

Look for any job with the UNAME COMSAT (and the JNAME IV).  If you find one, kill the job by typing:

<job number>X

Then, exit PEEK with the "q" command.

Now, send yourself a message:

:MAIL <your-uname>
<some message>
<control>c

You should see the message:

C Communications satellite apparently dead.
Re-launching, hang on... now in orbit!

Now, COMSAT should be running.  You can check with PEEK.

You also should see that your mail was delivered. Type:

:PRMAIL<enter>

to read (and optionally delete) it.