AIX 3.1 and IBM RS/6000 - Frequently Asked Questions (Part 1/3)

AIX 3.1 and IBM RS/6000 - Frequently Asked Questions (Part 1/3)

Post by Bjorn Engs » Tue, 31 Mar 1992 18:10:03

Archive-name: aix-rs6000-faq/part1
Version: 9

Frequently Asked Questions to AIX 3.1 and IBM RS/6000

This posting contains frequently asked questions (and answers) about the
IBM RS/6000 computer and AIX version 3.  All input is very wellcome,
please mail it to

The list is now split in three articles.  As some may have noticed, I
have only been sending this list out whenever I have had time to modify it
and that has not been often enough.  In the future I will send it
approximately once every month even if it means sending out an unupdated
version.  Please let your input continue, I am most thankful for all of it.

The list is posted to comp.unix.aix, news.answers and bit.listserv.power-l.
The latter is gateway'ed to POWER-L on bitnet.

The posting is organized as a digest, so popular newsreader programs
should be able to easily look up each item - at least hitting ^G in rn
will get you the next one and rn is what I happen to use.  In nn, the
command 'G %' will get you to the next.

I added lines of underscores before each major Subject: line to make a more
legible paper print.  If you see a From: line it means that whatever follows
is mostly an unedited version of the input I have received, and that I have not
verified its contents.  If there is no From: line, I hopefully know what
I am talking about, and the entry is probably edited entries from various

All entries are numbered with major and minor subject number, e.g.  3.05, and
they have a Date: that does not necessary have any important information.
If the subject is preceded by an asterix, that entry has been changed or
added since the last time.

The comp.unix.aix group is really for AIX on the four platforms, RT, PS/2, 370
and RS/6000, but it has 90% or more of its traffic covering AIX 3.1 and the
RS/6000.  The newsgroups and
have postings on the PC/RT, mostly hardware and AOS 4.3, and on PS/2
hardware respectively.  There doesn't seem to be a group covering 370

This article only covers AIX 3.1 and the RS/6000, except when specifically

If you post questions to comp.unix.aix, please be sure to indicate:

- Your machine type (not all questions are to the RS/6000)

- Your exact AIX version number, i.e. AIX 3.1 is NOT sufficient, whereas
  AIX 3.1.5 or AIX 3.1 with the 3005 update is.

All contributors are mentioned towards the end of this article.
Subject: Contents
Date: Tue, 10 Sep 91 12:37:58 GMT

Contents of this list, issue 7:

1.    The C Environment
1.01  I cannot make alloca work
1.02  How do I compile my BSD programs?
1.03  Isn't the linker different from what I am used to?
1.04  How do I link my program with a non-shared /lib/libc.a?
1.05  How do I make my own shared library?
1.06  Linking my program fails with strange error, why?
1.07 *What's with malloc()?
1.08  Why does xlc complain about 'extern char *strcpy()'
1.09  Why do I get 'Parameter list cannot contain fewer ....'
1.10  Why does xlc complain about '(sometype *)somepointer = something'
1.11  Some more common errors
1.12  Can the compiler generate assembler code.
1.13 *Curses
1.14  How do I speed up linking?
1.15  What is deadbeef?

2.    Fortran
2.01  I have problems mixing fortran and C code, why?
2.02  How do I statically bind fortran libraries and dynamically bind C
2.03  How do I check if a number is NaN?

3.    The AIX operating system - what is it?
3.01  I am used to Unix systems programming, why should I learn SMIT?
3.02  What is the Object Database.
3.03  How do I get rid of the verbose error messages?
3.04 *How do I make an informative prompt in the shell?
3.05  How do I import an /etc/passwd or /etc/group file from another box?
3.06 *How do I put my own text into InfoExplorer?
3.07  Who has a termcap/terminfo source for aixterm or the HFT console?
3.08  How do I put multiple backups on a single 8mm tape?
3.09  Which release of AIX do I have?
3.10 *Some known problems, telnet, accounting, who
3.11  Other hints, fsck of /, X-windows and alt-cntl-backspace
3.12  How do I shrink /usr?
3.13  How do I shrink the default paging space on hd6?
3.14  I know neither Unix nor AIX - where do I find more information?
3.15  How do I backup a multi-disk volume group?
3.16  How do I see/change system parameters like number of processes per
3.17  My /dev/null seems to have disappeared or become a plain file, why?
3.18  The swapper seems to use extreme amount of paging space, why?
3.19 *How much should I trust the ps memory reports?
3.20 *How do I do remote backup?

4.    Public Domain software.
4.00 *How do I find PD software?
4.01 *Are there any ftp sites?
4.02  GNU Emacs
4.03 *GNU C
4.04  Perl
4.05  X-Windows
4.06  Bash
4.07  Elm
4.08  General hints
4.09  Kermit
4.10  Gnu dbm
4.11  tcsh
4.12  Kyoto Common Lisp
4.13  TCL
4.14  Expect

5.    Third party hardware
5.01  Disk/Tape/SCSI
5.02  Disks.
5.03  Memory
5.04  Others
5.05  IBM List of third party products

6.    Third party hardware
6.01 *C++ compilers

7.    Miscellaneous other stuff.
7.01  Can I get support by email?
7.02  Some RS232 hints
7.03  VT100 keybindings for aixterm

8.    How do I get this by mailserver or ftp?
Subject:  1. The C Environment.
Date: Thu, 02 Jan 92 12:47:21 GMT

Contrary to many people's belief, the C environment on the RS/6000 is not very
special.  The C compiler has quite a number of options that can be used to
control how it works, which "dialect" of C it compiles, how it interprets
certain language constructs, etc.  InfoExplorer includes a Users' Guide and
a Reference Manual.

The compiler can be invoked with either xlc to invoke it in ANSI mode and cc
to invoke it in RT (i.e. IBM 6150 with AIX 2) compatible mode.  The default
options for each mode are set in the /etc/xlc.cfg file, and you can actually add
another stanza and create a link to the /bin/xlc executable.

The file /usr/lpp/xlc/bin/README.xlc has information about the C compiler, and
the file /usr/lpp/bos/bsdport contains useful information, in particular for
users used to BSD.

The file /etc/xlc.cfg also shows the symbol _IBMR2 that is predefined, and
therefore can be used for #ifdef'ing RS/6000 specific code.

Subject:  1.01 I cannot make alloca work
Date: Tue, 10 Sep 91 10:33:06 GMT

A famous routine, in particular in GNU context, is the allocation routine
alloca().  Alloca allocates memory in such a way that it is automatically
free'd when the block is exited.  Most implementations does this by adjusting
the stack pointer.  Since not all C environments can support it, its use
is discouraged, but it is included in the xlc compiler.  In order to make the
compiler aware that you intend to use alloca, you must put the line

#pragma alloca

before any other statements in the C source module(s) where alloca is
called.  If you don't do this, xlc will not recognize alloca as anything
special, and you will get errors during linking.

In earlier releases of the C compiler, alloca did not work well with the
optimizer turned on (-O flag), but this problem is solved now.  The fix
was probably in release 1.1.3 of xlc.obj, it is for sure in 1.1.5.

Subject:  1.02 How do I compile my BSD programs?
Date: Tue, 10 Sep 91 10:00:00 GMT

The file /usr/lpp/bos/bsdport contains information on how to port programs
written for BSD to AIX 3.1.  The contents of this file can actually be very
useful for others as well.

A quick cc command for most "standard" BSD programs is:

  $ cc -D_BSD -D_BSD_INCLUDES  -o [loadfile] [sourcefile.c] -lbsd

If your software has system calls predefined with no prototype parameters,
also use the -D_NO_PROTO flag.

Subject:  1.03 Isn't the linker different from what I am used to?
Date: Tue, 10 Sep 91 10:00:00 GMT

Yes.  It is not at all like what you are used to:

- The order of objects and libraries is normally _not_ important.  The linker
  reads _all_ objects including those from libraries into memory and does
  the actual linking in one go.  Even if you need to put a library of your
  own twice on the ld command line on other systems, it is not needed on the
  RS/6000 - doing so will even make your linking slower.

- One of the features of the linker is that it will replace an object in an
  executable with a new version of the same object:

  $ cc -o prog prog1.o prog2.o prog3.o          # make prog
  $ cc -c prog2.c                               # recompile prog2.c
  $ cc -o prog2.o prog                 # make from prog
                                                # by replacing prog2.o

- The standard C library /lib/libc.a is linked shared, which means that the
  actual code is not linked into your program, but is loaded only once and
  linked dynamically during loading of your program.

- The ld program actually calls the socalled binder in /usr/lib/bind, and you
  can give ld special options to get details about the invocation of the binder.
  These are found on the ld man page or in InfoExplorer.

- If your program normally links using a number of libraries (.a files), you
  can 'prelink' each of these into an object, which will make your final
  linking faster.  E.g. do:

  $ cc -c prog1.c prog2.c prog3.c
  $ ar cv libprog.a prog1.o prog2.o prog3.o
  $ ld -r -o libprog.o libprog.a
  $ cc -o someprog someprog.c libprog.o

  This will solve all internal references between prog1.o, prog2.o and prog3.o
  and save this in libprog.o  Then using libprog.o to link your program in
  stead of libprog.a will increase linking speed, and even if someprog.c
  only uses, say prog1.o and prog2.o, only those two modules will be in your
  final program.  This is also due to the fact that the binder can handle
  single objects inside one object module as noted above.

  If you are using an -lprog option (for libprog.a) above, and still want
  to be able to do so, you should name

read more »


AIX 3.1 and IBM RS/6000 - Frequently Asked Questions (Part 1/3)

Post by Bjorn Engs » Tue, 31 Mar 1992 18:26:10

Archive-name: aix-rs6000-faq/part3
Version: 9

 This article should be concatenated to part 1 and 2.

Subject: *5.   Third party products
Date: Tue, 10 Sep 91 10:00:00 GMT

 Editors note: Since my company does not use third party hardware, the
 entries in this section are only edited for formatting and for the purpose
 of not being like advertising.                                 /Bjorn.

Some information in here seems rather outdated......

Subject:  5.01 Disk/Tape/SCSI
Date: Tue, 10 Sep 91 10:00:00 GMT
From: anonymous

- Most SCSI disk drives work (IBM resells Maxtor, tested Wren 6&7 myself)

- Exabyte: Unfortunately only the ones IBM sells are working

- STK 3480 "Summit": Works with Microcode Version 5.2b

Subject:  5.02 Disks.
Date: Tue, 10 Sep 91 10:00:00 GMT

For third-party disks for the RS6000, I can recommend:  Ken Been at
National Peripherals, (708) 325-4151.

Subject:  5.03 Memory
From: bl...@VM.UoGuelph.CA (Doug Blain)
Date: Tue, 10 Sep 91 10:00:00 GMT

I have received a FAX from Kingston Technologies on SIMM memory upgrades for
the RS6000 (model 320/520 only so far). They are complete replacements for the
installed SIMMs from IBM ( you get to keep the IBM SIMMs and perhaps use them
elsewhere). They have a 16, 32 and 64 MB range of kits. The quoted list prices
are:  16 MB SIMM Kit   $3995
      32 MB SIMM Kit   $8995
      64 MB SIMM Kit  $21,585
   One option they mention in their letter is to purchase an additional memory
card from IBM (type S1 or higher) and populate it with the new memory, since
the RS/6000 will support two memory cards. The list price for the IBM 16mb
SIMMs is $9520 (however our SE is hinting at price reductions of 25% soon).
   Kingston Technologies can be contacted at 714-435-2600. Standard disclaimers association, benefits, etc.

Subject:  5.03 Memory
From: (Dick Karpinski)
Date: Tue, 10 Sep 91 10:00:00 GMT

Dick Verling at 415-381-2081 offers a 64MB upgrade for a bit over $5k.

Subject:  5.04 Others
From: anonymous
Date: Tue, 10 Sep 91 10:00:00 GMT

IBM RISC System/6000 Interface Products

National Instruments Corporation announced April 13 a family of
instrumentation interface products for the IBM RISC System/6000 workstation
family.   The interface family consists of three products that give the RISC
System/6000 connectivity to the standards of VMEbus, VXIbus and GPIB.
For more information, contact National Instruments Corporation, 512-794-0100 or

Subject: 5.05 *IBM list of third party products
Date: Tue, 12 Nov 91 18:30:33 -0800
From: (Marc Pawliger)

[ This entry is not edited in any way.  Ed. ]


Here is the November update for the catalog of third-party products for
the Risc System/6000 - disks, tape drives and memory sections.

The same disclaimers I posted the last time I posted this list are there
again - go down a few pages to see them in official-ese.  Also the author
requests that people only contact her via the email address listed here - or by fax (416) 941-6013 attn. B. Brett, and
not by phone.


+  Marc Pawliger    IBM Advanced Workstations Division    Palo Alto, CA   +
|   Internet        UUCP  uunet!ibminet!marc  |
|    IBMinet         phone  (415) 855-3493      |
+       VNET  MARCP at AUSTIN              IBM phone  T/L 465-3493        +



                                                       November 4, 1991

                                                          Barbara Brett
                                     National Support Centre -- Central
                                                        IBM Canada Ltd.
                                                           Internet ID:


    IBM CUSTOMERS: Please ask your IBM representative to obtain the latest
    version of this document for you.


    This document is on the AIXTOOLS disk as part of OEMHW PACKAGE.  To get
    the document on-line, key in


    To be sure of getting updates to this document, key in



    Your comments, suggestions, and corrections are  welcomed and appreciated.
    If you know of additional products or  dealers that  should be included in
    this document, please include the following information:

        o   Company name, mailing address, telephone and FAX numbers

        o   Product description and function

    Please send your comments, suggestions,  corrections, or additions to your
    choice of the following:

        o   the Internet id

        o   FAX number  (416)  941-6013  (attention  "B.  Brett  7th

        o   the IBM internal id BBRETT at CANVM2

    or to the mailing address

        Barbara Brett
        IBM Canada 7th floor
        P.O. Box 15, TD Center
        Toronto, Canada M5K 1B1


    This document has been developed as a quick reference for non-IBM RISC
    System/6000  hardware   products.  The  material  here   is   based on
    information obtained from the  hardware provider.  No  effort has been
    made  to  independently  verify  the   accuracy  of  the  information,
    including  any  information  relating  to the functions, quality,  and
    performance of the provider's  products  or services  as  well  as the
    availability  date.    The  customer is  responsible  for  determining
    whether any particular provider's  products or  services  are suitable
    for its own needs.

    Prices,  specific hardware or software  requirements  and availability
    dates  may be  obtained   by calling  the  vendor.   (In addition, the
    support provided  may   vary  from vendor  to    vendor).   Individual
    suppliers should be  contacted regarding  such items as  installation,
    support,  education, documentation, maintenance,  and  any other terms
    and conditions.

    This  document     does  not   constitute  an   expressed  or  implied
    recommendation or endorsement by the industry or IBM of any particular
    product,  company  or  technology,    but  is  intended  simply as  an
    information guide that will give a better understanding of the options
    available to  you.  The fact  that a company  does  not appear in this
    book does not imply that it is inferior to those listed.

    IBM takes no responsibility whatsoever  with regard to  the selection,
    performance,  or  use    of   the  products   listed   herein.     All
    understandings,  agreements,  or warranties  must take  place directly
    between the product suppliers and prospective users.


    The following terms are trademarks of the IBM Corporation:

    Micro Channel
    RISC System/6000


    Please see also listings under "SCSI adapter" for additional
    disk drive controller adapter products.

    7171 North Federal Highway
    Boca Raton, Florida 33487
    Phone (407) 997-6055
    FAX   (407) 997-6009

    The  CNT-ARR  adapter  supports  the  CORE disk array.   The
    CNT-MCK adapter supports two ESDI disk drives and 2 diskette

    2832-C Walnut Avenue
    Tustin, California 92680
    Phone (714) 730-9625
    FAX   (714) 730-7176

    The IX4000 IPI-2 disk controller adapter can have up to 8 MB
    of on-board cache.  This adapter controls a string of up  to
    8  IPI-2  disk  drives,  and supports a maximum IPI transfer
    rate of 27 MB/sec and a maximum Micro Channel bus data  rate
    of 40 MB/sec.


    In  some  cases,  the  vendors  listed below supply only the
    drive itself and not the additional hardware items  required
    to  install the drive inside the RISC System/6000.  Normally
    these additional items are available from the  IBM  Customer
    Service  (hardware  repair)  organization.    An  example of
    additional IBM parts required is given for one of the  disks
    in the Seagate listing below;  the total cost of these parts
    is  usually under $100 US.  It is critical to determine from
    the disk vendor and from IBM Customer Service exactly  which
    additional parts (if any) will be needed.

    211 River Oaks Parkway
    San Jose, California 95134
    Phone (408) 432-1700
    FAX   (408) 432-4239

    In Canada:
    Livewire    Toronto     (416) 798-3410    FAX (416) 798-3391

    o   760 MB unformatted (670 MB formatted)

    2145 Hamilton Avenue
    San Jose, California 95125
    Phone (408) 879-0300
    FAX   (408) 879-9330

    o   100MB and 200MB 3.5-inch drives, SCSI interface

    o   330MB and 665MB 5.25-inch drives, SCSI interface

    920 Disk Drive
    Scotts Valley, California 95066
    Phone (408) 438-6550)
        or 1-800-468-3472 (USA only)
    FAX   (408) 438-7852

        Seagate distributor BSM Ltd
            Phone 1-800-888-3475 (USA only)
        Seagate distributor Arrow

read more »


AIX 3.1 and IBM RS/6000 - Frequently Asked Questions (Part 1/3)

Post by Bjorn Engs » Tue, 31 Mar 1992 18:26:34

Archive-name: aix-rs6000-faq/part2
Version: 9

  This article should be concatenated to part 1

Subject:  3.08 How do I put multiple backups on a single 8mm tape?
From: (Cary E. Burnette)
Date: Tue, 10 Sep 91 10:00:00 GMT

There are two possible solutions to this, which both use the /dev/rmt0.1
device which is non-rewinding.


To put multiple backups on a single tape, use /dev/rmt0.1, which is a
no-rewind device, using either rdump or backup (both by name & inode work).
     Using rdump or backup "byinode" both generate the message that
the tape is rewinding but actually do not. This is an example that
would work on my system:

# rsh remote1 -l root /etc/rdump host:/dev/rmt0.1 -Level -u /u
# rsh remote2 -l root /etc/rdump host:/dev/rmt0.1 -Level -u /u
# tctl -f /dev/rmt0.1 rewind       # rewinds the tape

where I am implementing the command from host.
To restore a table of contents of the first I would use

# restore -f /dev/rmt0.1 -s1 -tv

where the -s1 flag tells restore to go to the first record it comes
across on the tape.
To get the second type in exactly the same once again.
Basically -s(Number) stands for - go to Number record from this spot.
It works pretty well.

If you have any questions or need any further information please let me know.

Mijan Huq
Fusion Research Center
University of Texas at Austin,


I use:
------------------- --------------------
CONTENTSFILE=`date |dd conv=lcase |sed -e 's/19//' |awk '{print $6 $2 $3}'`
set -x

backup -c -b 56 -$LEVEL -uf /dev/rmt0.1 /
backup -c -b 56 -$LEVEL -uf /dev/rmt0.1 /usr
backup -c -b 56 -$LEVEL -uf /dev/rmt0.1 /u
tctl -f /dev/rmt0 rewind

touch /usr/local/dumps/Contents.$CONTENTSFILE
echo "Dumping /" >>/usr/local/dumps/Contents.$CONTENTSFILE
restore -t -s 1 -f /dev/rmt0.1 >>/usr/local/dumps/Contents.$CONTENTSFILE
echo "Dumping /usr" >>/usr/local/dumps/Contents.$CONTENTSFILE
restore -t -q -s 1 -f /dev/rmt0.1 >>/usr/local/dumps/Contents.$CONTENTSFILE
echo "Dumping /u" >>/usr/local/dumps/Contents.$CONTENTSFILE
restore -t -q -s 1 -f /dev/rmt0.1 >>/usr/local/dumps/Contents.$CONTENTSFILE
tctl -f /dev/rmt0 rewind
I process the table-of-contents first  by a little program that does
common prefix encoding, and then compress.

This gives a able of contents file I can keep on-line until the tape
is reused.

Hope this helps.

        Steve Knodle
        Educational Resources Center
        Clarkson University

Subject:  3.09 Which release of AIX or other products do I have?
Date: Tue, 10 Sep 91 10:34:42 GMT

The command lslpp -h bos.obj will show all lines referring to the BOS, Basic
Operating System.  E.g.:

Option Name          State      Event      Date      Release         User Name

-------------------- ---------- ---------- --------- --------------- ----------
bos.obj              INACTIVE   COMMIT     02/03/90  03.01.0000.0000 root
                     INACTIVE   APPLY      06/25/90  03.01.0000.0001 root
                     INACTIVE   COMMIT     06/25/90  03.01.0000.0001 root
                     INACTIVE   APPLY      11/16/90  03.01.0002.0015 root
                     INACTIVE   COMMIT     11/16/90  03.01.0002.0015 root
                     ACTIVE     COMMIT     05/07/91  03.01.0005.0012 root

gives the history for the BOS lpp.  The last line, column four, tells that
this is release 3.1.5.  (Note that '3' in 3005 has nothing to do with '3' in
3.1.5 - we should stop calling the versions 3005, etc. and call it by its real
version number 3.1.5).

To see a listing of everything installed use lslpp -l '*', then use lslpp with
the -h option as above to get a history of a particular lpp.  Lpp, btw, means
Licensed Program Product.

Here is a description on IBM's release numbering scheme that was mailed to me
(PTF is an abbreviation for Program Temporary Fix):


The output of lslpp -h bos.obj shows a release number similar to

Contrary to your description and some other news items, this should be
referred to as 3.1.2 not 3002. The 3002 numbering is used to indicate
a PTF update tape. There are two types of PTF tapes 300x and 200x.
The 300x tapes are full PTF's to update all previous levels to 3.1.x level
The 200x tapes are incremental tapes and only apply to level 3.1.(x-1),
ie 2004 updates 3.1.3 to 3.1.4 and will not work with 3.1.2 at all,
whereas 3004 would update 3.1.0, 3.1.1, 3.1.2, and 3.1.3 upto level 3.1.4.
The release number is defined as follows, 03.01 is the major release number
shortened to 3.1 and the 0002 in the example is the minor release number.
Major releases are provided with full installable tapes, whereas minor
releases are obtained by applying a PTF update tape to a previous level
as indicated above. The fourth number is used by development and has no
validity(?) outside of developement ( note it may be of interest during
defect resolution ).

Subject: *3.10 Some known problems, telnet, accounting, who
Date: Tue, 17 Mar 92 15:17:16 GMT

There are known problems in telnetd in 3.1.2 and 3.1.3 (the RS/6000 may lock
when telnet'ing to it, use the 3001 telnetd or update to 3.1.5), accounting has
a number of problems, and 'who' often displays entries that do not correspond
to active sessions.

All this refers to release 3.1.2 and 3.1.3

The problem with telnetd seems to be solved in 3005, I do not know about
accounting, but the problem with who is known not to be solved.  The program
below can be used to fix up your /etc/utmp file:

--- cut here ---
#include <sys/types.h>
#include <utmp.h>
#include <fcntl.h>

main ()
        int     fd;
        struct  utmp    utmp;

        while (1) {
                if ((fd = open ("/etc/utmp", O_RDWR)) < 0)
                        exit (1);

                while (read (fd, &utmp, sizeof utmp) == sizeof utmp) {
                        if (utmp.ut_type == USER_PROCESS &&
                                        kill (utmp.ut_pid, 0) != 0) {
                                lseek (fd, - (long) sizeof utmp, 1);
                                utmp.ut_type = DEAD_PROCESS;
                                write (fd, &utmp, sizeof utmp);
                close (fd);
                sleep (60);


--- cut here ---

The program was posted by (John F. Haugh).  There
has also been a utmp program posted to comp.sources.unix, volume 25, issue
96 that also works on AIX 3.1.  It was posted by David W. Sanderson

Subject:  3.11 Other hints, fsck of /, X-windows and alt-cntl-backspace
Date: Tue, 10 Sep 91 10:00:00 GMT

- Normally alt-cntl-backspace will kill the X session.  If you add the
  -T option when initializing X, this will not happen.

- You should never run fsck on mounted filesystems, so you need to be in
  maintenance mode to run fsck on the root filesystem:

  1. boot from diskette
  2. select maintenance mode
  3. type /etc/continue hdisk0 exit (replace hdisk0 with boot disk if not
  4. fsck /dev/hd4

Subject:  3.12 How do I shrink /usr?
Date: Tue, 10 Sep 91 10:36:10 GMT
From: m...@bria.UUCP (Michael Stefanik)

  Editors note:

  I have not followed this procedure since I have not had the need.  Make
  sure you backup everything affected, and use at your own risk.   /Bjorn.

To "shrink" the /usr filesystem back down to an optimum size,
which could be about 140,000 blocks (70M), take the following steps:

        1. go into maintenance mode using the "/etc/shutdown -Fm"
           command; wait until the single user message is given
           by INIT.

        2. backup all of the files in /usr, using the command:

                # find ./usr -print | backup -iqvf /dev/rmt0

        3. unmount the /usr filesystem using the "/etc/umount /usr"

           The unmount may fail if you are using the korn or the bourne
           shell (ksh or sh); if this is the case you can switch to the
           C shell using the command "exec /bin/csh".  It could also
           be /usr/lib/errdemon that causes the unmount to fail.

        4. remove the /usr filesystem using the command "rmfs /usr";
           the filesystem MUST be unmounted in order to do this.
           the "dspmsg" command will not be found; ignore this error.
           edit /etc/filesystems, removing the /usr stanzas

        5. Remove the logical volume.

                # rmlv -f hd2

           We want to reuse hd2, since hd2 been hard coded in some scripts.

        6. Create a new hd2 logical volume and create a new filesystem on
           it. (NNN below is the number of 4M partitions, e.g. 18 for approx
           70 Mb).

                # mklv -yhd2 -a'e' rootvg NNN

                # crfs -v jfs -dhd2 -m'/usr' -Ayes -prw

        7. mount the new /usr filesystem using the "/etc/mount /usr"
           command; check it using the "df -v" command.

        8. restore the file using "restore -xqvf /dev/rmt0"

        9. Sync and reboot the system; you now have a smaller /usr

Subject:  3.13 How do I shrink the default paging space on hd6?
From: (Jaime Vazquez)
Date: Tue, 10 Sep 91 10:00:00 GMT

[ Minh Tran-Le <> sent me an updated version, ed.]

1. create a paging space to use temporarily
   mkps -a -n -s 20 rootvg  (this is a 20 partition - 80MB - swap space)
2. change characteristics of default paging space device hd6 so it
   is not used at next reboot
   chps -a n hd6
3. Edit /etc/rc.boot4 and change swapon /dev/hd6 to
        swapon /dev/paging00
4. remake the boot filesystem
        bosboot -a
5. shutdown and reboot
6. remove hd6 and create a new hd6 of smaller size
   rmps hd6
   mklv -y'hd6' -t'paging' rootvg 25   (It is IMPORTANT that you reuse the hd6.)
                                       (A lot less headaches later on.)
7. Reedit /etc/rc.boot4 so swapon is back to /dev/hd6
8. change current paging device (paging00) so it is inactive
   at next boot
   chps -a n paging00
9. remake again the boot filesystem
        bosboot -a
10. shutdown, reboot, remove paging00
11. current paging space is now reduced

Subject:  3.14 I know neither Unix nor AIX - where do I find more information?
Date: Tue, 10 Sep 91 10:00:00 GMT

Quite a number of questions posted to comp.unix.aix show that AIX is people's
first experience with Unix.  If this is the

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