X-Git-Url: http://git.ozlabs.org/?p=ppp.git;a=blobdiff_plain;f=FAQ;h=035da4b2456917090cbc68eb166786065c139538;hp=780ca6309b8fa257e35af4e7edc2a8b2f7a06616;hb=2b4ea140432eeba5a007c0d4e6236bd0e0c12ba4;hpb=9c9e0653fd77e0524be85f3a653909c5f07aff3f diff --git a/FAQ b/FAQ index 780ca63..035da4b 100644 --- a/FAQ +++ b/FAQ @@ -378,8 +378,10 @@ to pppd when using PAP authentication so that it can select the appropriate secret from /etc/ppp/pap-secrets. Microsoft also has a variant of CHAP which uses a different hashing -arrangement from normal CHAP. There is a client-side implementation -of Microsoft's CHAP in ppp-2.3; see README.MSCHAP80. +arrangement from normal CHAP. There is a client-side (authenticatee) +implementation of Microsoft's CHAP in ppp-2.3; see README.MSCHAP80. +In ppp-2.4.2, server-side (authenticator) support was added as well as +support for Microsoft CHAP v2; see README.MSCHAP81. ------------------------------------------------------------------------ @@ -607,3 +609,28 @@ if just with PAP using their login password (using the `login' option to pppd). If you do use `noauth', you should at least have a pppusers group and set the permissions on pppd to allow only user and group to execute it. + +------------------------------------------------------------------------ + +Q: When running pppd as a dial-in server, I often get the message +"LCP: timeout sending Config-Requests" from pppd. It seems to be +random, but dial-out always works fine. What is wrong? + +A: Most modern modems auto-detects the speed of the serial line +between the modem and the computer. This auto-detection occurs when +the computer sends characters to the modem, when the modem is in +command mode. It does not occur when the modem is in data mode. +Thus, if you send commands to the modem at 2400 bps, and then change +the serial port speed to 115200 bps, the modem will not detect this +change until something is transmitted from the computer to the modem. +When running pppd in dial-in mode (i.e. without a connect script), +pppd sets the speed of the serial port, but does not transmit +anything. If the modem was already running at the specified speed, +everything is fine, but if not, you will just receive garbage from the +modem. To cure this, use an init script such as the following: + + pppd ttyS0 115200 modem crtscts init "chat '' AT OK" + +To reset the modem and enable auto-answer, use: + + pppd ttyS0 115200 modem crtscts init "chat '' ATZ OK ATS0=1 OK"