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Troubleshooting ISP Connection Problems
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I will assume that this dialed your phone. This will not connect you to your ISP via PPP unless your ISP is incompetent. There is as yet no authentication. However, we can now use the debugging output of this command to determine what kind of authentication your ISP wants.



Which authentication scheme?

Look at the end of /var/log/ppp by typing

less /var/log/ppp

To page back, use ^B (Control-B) The space bar will page forward. Or, if you ran the tail -f command above look at the end of its output. You should see a bunch of messages from chat, telling you what it sends and what it receives from the far end. In this case, it will end when chat receives the "CONNECT" string

got it (CONNECT)

from your modem.

Then pppd will start reporting, and will probably give an error message. One possibility is the message containing the line Problem: all had bit 7 set to 0. This means that your ISP was not expecting you to negotiate PPP at this point. It almost certainly means that your ISP wants you to log on first.

You may at this point get no response from the remote system at all -- your system sends out LCP Config Requests but gets no response. Try replacing the \d\c in the above line with the word CLIENT, and try again. This indicates that you have an Windows NT RAS server as your ISP. In all of the discussions below, continue to replace \d\c with CLIENT.

Or, if one of the lines at the end of /var/log/ppp reported to be from pppd and had a line that started out with rcvd and then had text that looked something like

<auth pap>

or

<auth chap ...>

(As an example, here is one of mine:)

Jan 15 23:10:28 wormhole pppd[511]: rcvd [LCP ConfReq id=0x1
<mru 1524> <asyncmap 0xa0000> <auth pap> <pcomp> <accomp>
< 13 09 03 00 c0 7b 63 d6 e6>]

this means that they are ready to negotiate PPP and want to use PAP (CHAP) authorization, not login authorization. If so, skip ahead to the PAP/CHAP authorization section.

Login authorization

So ... Let's assume that they want login authorization (you got the bit 7 error message). Try (on one line)

/usr/sbin/pppd /dev/ttyS1 57600 debug connect "/usr/sbin/chat -v   ''  ATD5555555  CONNECT   ''  ogin:  <yourusername>  assword:  <yourpassword>"

where <yourusername>; is your user name on the remote machine, and similarly for <yourpassword>. Note that the <> surrounding the words yourusername and yourpassword are not to be included in your script. Note again that those are doubled apostrophes ' not single double quotes " inside the chat -v script, but are double quotes " surrounding it.

Again look in /var/log/ppp.

You should see chat logging you in (sending your remote name and your password). If not, look at what chat received from the far end to get a clue as to what it expected. For example, on some machines the login request comes via a Name: or Username: request instead of Login:. In that case, change the "ogin:" to "ame:" instead in the above command line.

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