QNX4 and TCP/IP

QNX Newsgroups (Archives) qdn.public.qnx4
21

“David Gibbs” <dagibbs@qnx.com> wrote in message
news:970rhl$rs1$1@nntp.qnx.com…

Chris Nasr <> cnasr@mechtronix.ca> > wrote:
Hello everyone,
well just to let everybody know the problem no longer exists, although I
can’t
say exactly why at the moment, (I’ll spend more time on that when I can)
I do
know that it had something to do with running “netmap -f” in the sysinit
file.
When I comment it out everything works just as it should (leading me to
believe
this problem always existed, I just never noticed before because I never
created nodes over 2)

If you had an incorrect netmap file, then the netmap -f will probably
break
things. It tells Net about what the physical hardware address for your
node
is, then Socket asks Net for this information. If this machine has had
different identities, and you didn’t update the netmap with appropriate
information each time you changed, that could cause a problem.

David,

I had lots of discussion by email with Chris, he assures me the
netmap file is empty (totaly blank). This is very odd i don’t understand
the logic behind this, it smells fishy.

In one of my email exchange with Chris we confirm that the arp
on Windows show the wrong MAC address for the node
he was trying to talk to. I suspected another machine with
the same IP address but that doesn’t appear to be the case.
Somehow it seems doing “netmap -f” on an empty netmap file
makes the TCP/IP stack use the wrong MAC address. ???

table

-David

QNX Training Services
dagibbs@qnx.com

22

Mario Charest <mcharest@antispam_zinformatic.com> wrote:

“David Gibbs” <> dagibbs@qnx.com> > wrote in message

I had lots of discussion by email with Chris, he assures me the
netmap file is empty (totaly blank). This is very odd i don’t understand
the logic behind this, it smells fishy.

In one of my email exchange with Chris we confirm that the arp
on Windows show the wrong MAC address for the node
he was trying to talk to. I suspected another machine with
the same IP address but that doesn’t appear to be the case.
Somehow it seems doing “netmap -f” on an empty netmap file
makes the TCP/IP stack use the wrong MAC address. ???

I’ve never heard of this being a problem with an empty netmap file –
only with a netmap file that contained an incorrect MAC address for
the machine – the incorrect one in the netmap file over-rode the
correct one from the hardware, and this screwed up TCP/IP.

-David

QNX Training Services
dagibbs@qnx.com

23

Weirder and weirder.
I was reading your messages (David & Mario) and I got to thinking that
something didn’t make sense.
So I went and ran “netmap -f” on the computer that was working, and low end
behold, it still works. So here goes,

I made “netmap -f” run in the sysinit file again.
Doesn’t work,
I made “netmap -f” run in the sysinit file, only with a 5 second pause between
Net.ether1000.
Doesn’t work,
Then I took it out of sysinit, rebooted, and immediatly ran “netmap -f” at the
command prompt
It still works.

Does anyone know why such a thing would happen? I’ve seen it once before in a
script file I made that copied a .boot file from a floppy to a disconchip (it
would give errors from the script, but not from the command prompt) But I never
figured out why.

I guess this is a whole new problem now. Sorry.


Chris Nasr
cnasr[at]mechtronix[dot]ca
Mechtronix Systems Inc.

24

Chris Nasr <cnasr@mechtronix.ca> wrote:

Weirder and weirder.
I was reading your messages (David & Mario) and I got to thinking that
something didn’t make sense.
So I went and ran “netmap -f” on the computer that was working, and low end
behold, it still works. So here goes,

I made “netmap -f” run in the sysinit file again.
Doesn’t work,
I made “netmap -f” run in the sysinit file, only with a 5 second pause between
Net.ether1000.
Doesn’t work,
Then I took it out of sysinit, rebooted, and immediatly ran “netmap -f” at the
command prompt
It still works.

Does anyone know why such a thing would happen? I’ve seen it once before in a
script file I made that copied a .boot file from a floppy to a disconchip (it
would give errors from the script, but not from the command prompt) But I never
figured out why.

Can you, maybe, capture the output of netmap before and after doing the
“netmap -f” in the sysinit, and by hand? Oh ya, also grab “sin in” in
there.

e.g. in the sysinit:
sin in > /tmp/nm
echo before >> /tmp/nm
netmap >> /tmp/nm
netmap -f
echo after >> /tmp/nm
netmap >> /tmp/nm

Can you post your sysinit file?

-David

QNX Training Services
dagibbs@qnx.com

25

(sigh) This won’t be hard to do, But here goes.
It seems over the last few days I have wasted the time of some very intelligent
people, and I must tell you I am extremely sorry for this, it seems in fact, that I
am a bit of a moron.

To Mario and David specifically I must tell you I am sorry, although I did not do it
intentionally, I lied to both of you when I said the netmap file was empty.

I was right, it was empty, it just wasn’t the right file, there was one in the /etc
directory, and that is the one I was looking at, but… as you guessed it, there was
one in /etc/config, and it had, quite clearly, 4 entries, one for node 3, for 4, for
5, and for node 6, all the ones I tested that didn’t work.

When I did the test David just told me of, to grab the info from netmap into a file,
it showed quite clearly that the MAC address for node 4 was exactly right, but that
after I ran “netmap -f”, there were now four entries, and the one for node 4 was no
longer right. So I tried “use netmap” and there was my mistake right in front of me.

-f Set the network node mapping table from the default mapfile
‘/etc/config/netmap’.

and so off I went, to find a file filled with mappings to machines that were
originally connected to the computer I took the HD copy of more then a year ago.

As I said, I’m sorry, I made a huge mistake and I wasted alot of peoples time, and
probably had some people wondering why logic wasn’t making sense.

I can honestly say I’m going to be paranoid to ever post here again without taking a
few weeks to check everything I can first.

Sorry,


Chris Nasr
cnasr[at]mechtronix[dot]ca
Mechtronix Systems Inc.

26

Chris Nasr <cnasr@mechtronix.ca> wrote:

It seems over the last few days I have wasted the time of some very
intelligent people, and I must tell you I am extremely sorry for this

Thank you for the apology and the final status.

-David

QNX Training Services
dagibbs@qnx.com

27

“Chris Nasr” <cnasr@mechtronix.ca> wrote in message
news:3A943767.7F382304@mechtronix.ca…

(sigh) This won’t be hard to do, But here goes.
It seems over the last few days I have wasted the time of some very
intelligent
people, and I must tell you I am extremely sorry for this, it seems in
fact, that I
am a bit of a moron.

No need to be so hard on yourself. A little bit of self-indulgence
seems in order :wink: Please fell free to come posting here, you had
a positive attitude throught out your ordeal, I dig that … :wink:

  • Mario