Bug 7760

Please upgrade to ppp-2.3.10-3 if you have not already done so.

yes, i did upgrade to ppp-2.3.10-3, and still nothing.  I also upgraded to the
latest rawhide initscript package (as of last week) after someone suggested to
try that, and still nothing.

OK, this is going to require an strace to fix.  It's not at all
obvious what is happening.

In /etc/sysconfig/network-scripts/ifup-ppp go near the bottom and
change the "exec /usr/sbin/pppd ..." instances to
"exec strace -f -o /tmp/ppp.trace /usr/sbin/pppd ..."
and then send me the resulting /tmp/ppp.trace via email.

Ok, i replaced the lines.  Now i get error msgs when i try to start it up.
Using usernet, it tells me 'Failed to start interface', and if i use 'ifup
ppp0' at a prompt it says 'Delaying ppp0 initialization.'

Do you have strace installed?

yes i do, and i even gave the full path name to it in the script, and still got
the error msgs.  I did do a strace run on wvdial straight from the command
line, so i know it works, but it wouldn't work in the script.

Is /tmp/ppp.trace created?

no, it isn't.

ok, stupid me, i got the script to run (had to change the file permissions),
and i got it to run with strace.  Still gave me an error msg:  "Failed to
activate ppp0 with error 1".  I was able to get a strace output, this is all i
got:

4019  execve("/usr/sbin/pppd", ["/usr/sbin/pppd", "-
detach", "lock", "modem", "crtscts", "asyncmap", "00000000", "defaultroute", "us
epeerdns", "user", "morhop", "remotename", "ppp0", "/dev/modem", "115200", "ippa
ram", "ppp0", "linkname", "ppp0", "noauth", "connect", "/usr/sbin/chat  -
f /etc/sysconfig/network-scripts/chat-ppp0"], [/* 23 vars */]) = 0

ok, three things:

one:  someone suggested to me to try using kppp.  I did, no sych luck, still
hangs.

two:  took my box to my local LUG meeting.  Someone was able to get it to dial
out and hook up by using minicom to dial, then exiting w/o resetting the modem
and running pppd w/ no options.  Once we manually set defaultroute to ppp0, had
no problems pinging/doing DNS lookups, etc. to other hosts.

three: i did a strace of 'ifup ppp0' set up using chat and captured it.  Shall
I send it?

Yes, please send the output of strace.  Error 1 from pppd is a serious error,
such as running out of memory.  If you turn the volume on the modem high enough,
does it sound like the connection is picked up on the other end?  If so, does
the handshaking complete?

ok, im sending you the output of a strace i just did on ifup itself.  I let it
cycle three times before i crtl-c'd it.  this time it gave me an error of 32.
as far as the modem volume goes, it doesn't even pick up or open the line to
dial out. Watching the modem, I can see the lights as it initializes, but then
it does nothing but cycles like when you get a busy signal or some
other 'normal' dialing error.

I had the same problem under RedHat 6.1.  Another post suggested adding "noauth"
to /etc/ppp/options.  This allowed pppd to dial out, though I had to do some
work by hand to get a working routing table.

Just tried that, still no luck.

Looking at the output of the strace, I can see chat being started properly, the
modem responding properly to the ATZ init string, and the chat program
attempting to dial out.  At that point it appears that chat times out waiting
for a response from the modem.

If it doesn't start dialing, then the modem isn't receiving the command in a
form that it's expecting -- perhaps with a \n appended to the strings written
to the modem.

If it is dialing, and you can hear the handshake begin before chat times out,
you might try increasing the timeouts value passed to chat (with the -t flag)
to see if being more forgiving of delays helps things.

ok, the modem isn't dialing, so im gonna try the adding the '\n's.
Ok, in my chat-ppp0 file, i stuck a '\n' on both the 'atz' line and the 'atdt'
lines.  still no dialing.  the only difference this time is that chat logs the
actual sending of the 'atdt' to syslog.  The original way didn't log it.

Are you sure there isn't some kind of interrupt conflict here?  This sounds like
the sort of strangeness you get with those.

What kind of modem is this?  What do you get from ATI0, ATI1, ATI2, etc.?

Under /proc/interrupts, my serial driver is listed using IRQ 4, and
under /proc/ioports it is using memory range 02f8-02ff.

I have a Zoom 56K external modem, model # 2849

as far as the ati* commands, i get this (this was done in minicom, so i know
the modem works ok):

ati0:  56000
ati1:  255
ati2:  OK
ati3:  V.0516-K56_DLS-A Z201
ati4:  a007840284C6002F
       bC60000000
       r1005111151012000
       r3000111170000000
ati5:  022
ati6:  RCV56DPF L8570A Rev 9.10/9.10
ati98: FLASH PNP MSG DR
       V80 V8BIS
ati99: 000300A3

Created attachment 135 [details]
strace output

I hunted around Zoom's web site and found their hints sheet for Unix machines at
http://www.zoomtel.com/techsprt/linuxfiles/unix.txt
It suggests adding "&C1 &D2" to your modem init string.  You might also try
"S13=10", which will force the modem to accept commands terminated with just a
newline character.

ok, THAT DID IT!!!   seems i have to add an &F (restore to factory settings) to
the init string for it to dial... running 5.x and 6.0 i never had to do that.
Why is that?

The defaults used by wvdial (ATQ0 V1 E1 S0=0 &C1 &D2 S11=55 +FCLASS=0) are
probably causing problems with your modem.  (Not the "&C1 &D2" part, of course,
if that's helping things work properly.)  Other tools we ship usually use a
simple "ATZ" to reset the modem, and it certainly looks like one of these other
settings is causing things to not work.

Until (if ever) wvdial supports modem brand-specific settings, this'll have to
just be in my list of weird things to check when this turns up again.

Thanks!