During the holiday
period, traffic on HP3000-L tends to be down a bit and also tends to the
off-topic and wildly off-topic. This year was no exception. However, there was
still plenty of technical content to allow me to pick and choose what I
considered the most interesting and most useful items for net.digest and
Hidden Value.
There are two recent
trends on HP3000-L that I want to briefly mention, one disturbing and one
puzzling. It seems to me that the some of the off-topic threads have become
more personal and more mean spirited than in the past. HP3000-L has always been
noted for its civility when compared to most other listservers out in the
ether. It would be more than just a shame if that changed. Please think about
this before making a possibly inflammatory posting. The other trend I have
noted, and puzzled over, is the number of first time posters who have clearly
never seen an HP 3000 until just recently, much less tried to use one. What
does this mean?
Finally, before we get
going, December saw a very interesting thread over on the OpenMPE list
(subscribe at www.openmpe.org) about MPE
licensing for a platform emulator. If you have any interest in MPE continuing,
especially on an emulator, you should sign up for this list and contribute your
thoughts.
As always, I would like to hear from readers of net.digest and Hidden Value. Even negative comments are welcome. If you think I’m full of it or goofed, or a horse's behind, let me know. If something from these columns helped you, let me know. If you’ve got an idea for something you think I missed, let me know. If you spot something on HP3000-L and would like someone to elaborate on what was discussed, let me know. Are you seeing a pattern here? You can reach me at john@burke-consulting.com.
How to create a scratch pad
area on your HP 3000
The question seemed simple enough, "I
want to create a directory off the root, say /transfer, and allow any user
anywhere on the system full access to it. I want any user to be able to place
files in this directory, as well as allowing any user to delete any files that
exist in the directory. I thought my answer was 'ALTSEC
/transfer;reppair=(CD,DD,RD,TD:@.@)' but that didn't do the trick. What can I
do?"
The first "answer" was
I can never remember :ALTSEC ACD syntax
details. But fortunately POSIX chmod
makes your request quite easy:
:XEQ CHMOD.HPBIN.SYS "777
/transfer"
This created a directory like /tmp that
anyone could deposit a file into. However, the files created in this manner are
not automatically accessible to other users.
The follow on "answer" was
Your ALTSEC does work, however, perhaps you
are forgetting to do an ALTSEC on every file placed in the /transfer directory
to allow other uses to access those files. For example,
:ALTSEC
/transfer/foo;reppair=(r,w,x,racd:@.@)
or,
:XEQ CHMOD.HPBIN.SYS "777
/transfer/foo"
will permit any user to do anything to
"foo" in the /transfer directory.
But, again, this does not answer the
original question. The first suggestion will let anyone CREATE a file in
/transfer and the second suggestion will let anyone do anything to the file
"foo" in /transfer, but neither creates a repository that will let
anyone create a file in it and let anyone else do anything to the file without
an extra step. Here, however, is a way to do what was originally asked by
making use of MPE's security features along with the POSIX symbolic link
feature.
1. create an account with
access=(r,w,l,a,x:any)
2. create a group in this account with
access=(r,w,l,a,s,x:any)
3. either use passwords or remove IA, BA
access for security
4. create a symbolic link, NEWLINK
/transfer,/ACCOUNT/GROUP;symbolic
You now have scratch space that anyone can
use without restriction.
A command file tip you may
have forgotten
We have probably all created a command file
such as PRINTFILE with a first line something like
parm sfid, dev=200, pri=8, copies=1
...
And use it like this to print two copies of
spoolfile ID O1234 using the default values for "dev" and
"pri"
printfile o1234,,,2
Michael Anderson and Greg Chaplin reminded
us, in answering someone's question, that an alternate format could just as
easily be used to keep you out of comma hell:
printfile o1234 copies=2
Something to consider if
you are using Samba across the Internet
Mark Bixby provided this helpful hint. I've
been doing some Samba 2.2.5 performance testing the past few days, and I have
found that adjusting one of the TCP timers in NMMGR can make a substantial
performance improvement, at least in my DSL <-> Internet
<->Cupertino environment.
As I was doing large cut/paste downloads
(~50MB) via Samba, I noticed that the status icon for the VPN software needed
to access the HP intranet was showing long pauses (5-10 seconds) where no
packets were being received. I then cranked up the Samba debugging level in
smb.conf and also added some extra debugging code of my own. I was able to
determine that it was the send() sockets function that was experiencing the
long pauses. I.e. Samba was processing
without any undue delays, but was being blocked waiting for the MPE TCP stack
to complete the send() operation.
Because my DSL connection is slow compared
to the network connection of the Samba server, the MPE TCP stack would
eventually time out waiting for an ACK, pause according to the exponential back
off algorithm, then try to resend the un-ACKed packet. These retry pauses
quickly double to rather large amounts of time that greatly exceed what is
needed to retransmit over "modern" TCP networks, thus the remote
client ends up experiencing large delays waiting for retried packets. For
greater detail about this, see the HP3000-L archives for numerous postings from
James Hofmeister.
Adjusting the TCP timers will change the
performance of a TCP send(). Go into NMMGR and navigate to the
NETXPORT.GPROT.TCP screen. Change "Retransmission Interval Lower Bound
(Secs)" to the minimum of 1. Then validate,
exit, followed by a networking restart or a reboot. You should now see better
Samba performance.
Caution, though, your mileage may vary.
Also, I can imagine certain configurations where you wouldn't want to lower the
retransmission lower bound, i.e. if your 3000 predominantly talks to remote TCP
clients with really slow network connections.
Donna Garverick graciously provided the URL
for one of James' postings that I have found particularly useful in the past. I
used it to solve a problem I had using Lars Appel's port of htDig with Apache.
Mark's tip and James' posting (see
http://raven.utc.edu/cgi-bin/WA.EXE?A2=ind0112A&L=hp3000-l&P=R49)
should be added to your tips folder.
In case you missed it
Courtesy of Gary Jackson and Bill Cadier, if
you use Mirror/iX and plan to install MPE/iX 7.5, be sure to install GR patch
MPEMXC6B or its successor. Failure to do so will lead to unpleasant
consequences.
This migration stuff is not
easy to plan for
Many people have been asking questions like
this that appeared recently on HP3000-L: "I'm trying to help someone size
an HPUX system to replace their HP 3000/969/100. Has anybody done something
similar? What HPUX box did you go to? Anybody have any benchmarks that can be
used to compare performance amongst various HP 3000s and 9000s?"
If you are going to replace your
applications with purchased applications, then your vendor of choice should be
able to help you size the hardware you will need. For example, if you plan to
join the big boys and move to something like SAP R/3, both SAP and your
hardware vendor of choice, HP for example, have detailed sizing programs
available to help you. From personal experience, I recommend you and your
management be sitting down when you read the results.
Birket Foster, of Platinum Partner M.B.
Foster Associates, had this take on the question: "In the matter of
performance, it depends. Is the application moving or being replaced? If it is
being replaced by off the shelf software (COTS), then there may be performance
characteristics available from the vendor. If you are moving it, there are
greatly differing performance footprints depending on the number of
connections, the workload including OLTP and batch jobs and the database
chosen. You must clearly understand the workload and the pieces that make it up
before anyone can give an estimate or model it. HP has a benchmark center as
part of the migration center which may help with estimates."
Alan Yeo added, “Benchmarking is really only
useful if the benchmark actually benchmarks something that you do. It is
utterly useless to anybody else other than as a vague finger in the air gauge.
In the above example what you have is a measure of how that particular vendor
chose to migrate/re-write their application. There are just too many variables
to make it useful to anybody else.
“While there are some measures that may give
you some sort of guidance as to the size of HP9000 you might need, in reality
its only when you have done the work that you will know how efficient what you
have migrated is, and therefore what configuration you will need. And as I
suspect for those companies migrating more than a single standalone application
what you actually end up running could be spread across several servers, and
you will never have a box that was running everything exactly as your HP3000 was.
“So by all means gather together as much
anecdotal benchmark information as you can. Accumulated together it will give
you a guide to the ballpark you will be operating in. But would I go out and
order a processor based on other peoples results? Never. Also most migrations
are going to take a reasonable amount of time so why worry about sizing the
production system now? Instead, worry about the size and cost of the
development/testing box and tools that you need now.”
From the seriously cool
department
Mark Wonsil has ported text2pdf, a freeware
text to Adobe PDF converter program written by Phil Smith of the Electronic
Publishing Research Group. Actually, he did it some time ago and I'm only just
now checking it out. Check it out for yourself at http://invent3k.external.hp.com/~MGR.WONSIL/text2pdf.html
Remote reboot
Remote reboots are something I have not
thought much about lately because I have had Telamon's Console Engine available
giving me remote consol access. So, when someone asked about ways to do remote
reboots, it was interesting to see all the possibilities that now exist.
Christian Lheureux offered the classic
solution: "Go to the console issue CTRL-B and then enable the remote
console with ER. Of course, you need to have a modem ready in auto-reply mode
and a phone line."
Jonathan Backus added, "Another great
way is the WebConsole".
Cory Black suggested using a PC equipped
with PCAnywhere as the system console. I've successfully used this technique
also, although it requires that you can access your corporate LAN remotely.
John Korb suggested using a power switch
that you can access via Telnet or web browser and to power cycle the CPU. If
you have AUTORESTART (an extra cost software product) or AUTOBOOT configured,
your system will come back up. Kind of crude, but workable.
In the same vein, Gavin Scott noted,
"If you have one of the recent A/N class systems then you can also turn
the system power on and off from the built-in Service Processor I believe. The
externally accessible power switch turns out to be little more than a hint to
the system."
Finally, Chris Bartram reminded everyone
about the HP3000-L FAQ (available at www.3k.com) and item 3.1.4, "How can
I make the 3000 reboot automatically if it crashes?" that shows how to
setup your 3000 to reboot automatically when it crashes (no additional software
needed - just FOS).