6. 故障排除

您已经阅读了本文档、《Modem-HOWTO》和《PPP Howto》，并且相当确定您的调制解调器与可用的驱动程序之一匹配，但它仍然无法工作？在这个过程中有很多环节可能会出现问题。

Linux 通常会维护网络连接的记录，这些记录对于解决问题非常有用。它们的特定文件名随 Linux 发行版和拨号软件而异，但系统日志文件 /var/log/messages、/var/log/syslog 等应该至少提供一些信息。

为了您自己的故障排除以及向列表寻求帮助的查询，如果您收集下面请求的信息将会很有用。以 root 用户身份，切换到调制解调器安装脚本所在的目录，并开始如下所示的脚本记录。在此脚本以 "exit" 终止后，将其从您的 Linux 分区中复制出来，以便传输到可能帮助您的列表。

(下面，# 是解释性注释。)

# start the recording,
script ModemTest.txt 
# type in as much info on your Modem card as you have
echo winmodem name, manufacturer, designation, and chip if possible
# this gives your current kernel version
uname -r
# this gives information on your serial ports
setserial -agv /dev/ttyS*
# this information on your interrupts (irq)
cat /proc/interrupts
# show the contents of your module installation script (insert script name):
cat ScriptName
# Check if your script is executable:
ls -l ScriptName
# a response is OK if it has "x" such as below:
# -rwxrw-rw-  1 root     root  654 Jan  6  2000 ltinst
# otherwise make it executable with:
chmod o+x ScriptName
# verify with
ls -l ScriptName
# if ScriptName has not been successfully run before under this kernel
# run it with:
./ScriptName
# what is the symbolic link /dev/modem set to:
ls -l /dev/modem
# What is the DeviceName specified in the ScriptName (/dev/ttyS14 or ...?)
echo DeviceName
# what is your modem driver name? Something like DriverName.o
# with the ".o" indicating it is a compiled binary
echo This is my DriverName.o
# if should have been inserted in the Modules Path
# Try to display it there with:
find /lib/modules | grep DriverName
# Is DriverName among the modules installed in the running kernel?
lsmod
# if not try a simple insertion:
insmod ./DriverName.o
# or if it was in the Modules Path, the following will suffice:
insmod DriverName
# check for insertion:
lsmod
# if not inserted, try forcing:
insmod -f ./DriverName
# list your inserted modules again.
lsmod
# If DriverName is NOT listed, 
# their is an incompatibility between modem hardware, driver and kernel.
# Further effort will be of No use.
# If DriverName is listed, let's do a bit more information.
# You may first wish to rerun the configuration utility 
# used to setup dial-in connections for your Linux installation.
# Remember to edit your PassWord from this record later.
# You will probably be queried for the following information 
# which you should have ready:
#Port to be used (/dev/modem or /dev/ttySn),Dial-inNumber, UserName, PassWord. 
# Run your configuration utility.
YourSetUpConf
# To stop recording 
exit

如果拨号不成功，请在此处附加来自您的日志文件的记录。例如，下面是一个来自 Debian Linux 系统的 /var/log/syslog 的节选。