Những câu hỏi thường gặp về Linux
•
Make sure that the serial port và modem are operating correctly. Using a program like minicomm or
kermit
, you should be able to send
AT
commands to the modem và receive the
OK
string in response
from the modem.
•
Enter the primary và possibly secondary Domain Name Server IP addresses in the [/etc/resolv.conf]
file, using dotted quad notation, with the
nameserver
label. For example:
order hosts,bind
nameserver 196.182.101.103
nameserver 196.182.101.104
The nameserver addresses in the example above are examples only. They don’t correspond to actual
network hosts. The first line,
order hosts,bind
, tells your networking software, when it resolves
network domain addresses, to first look in the [/etc/hosts file], và then use the bind service; i.e., the
DNS servers, which are specified on the lines that begin with nameserver.
•
Locate the chat script that PPP will use to dial the modem và connect to your ISP. In many systems,
this is either in the [/etc/chatscripts] or [/etc/ppp] directory, và will be called [provider] or something
similar. You can store a
chat
script anywhere, provided that you tell pppd to use it rather than the
default script. Refer to the chat và pppd manual pages, và the information below, for details. Here is
a sample
chat
script:
ABORT
BUSY
ABORT
"NO CARRIER"
ABORT
VOICE
ABORT
"NO DIALTONE"
""
ATDT
<your_isp’s_phone_number>
ogin
<your_user_name>
word
<your_password>
This is a chat program for a simple, script based login. The chat program uses the pair of strings on
each line as a match/response pair. When it starts, it sends the string
“ATDTyour_isp’s_phone_number,” where you have substituted the actual phone number of course. It
then waits for the string
ogin
(a substring of the word
login
) và sends your user name. It then waits
for
word
(a substring of
password
) và sends your password. If your ISP uses a different login và
password prompts, và any additional prompts, you will need to edit the script accordingly. Again,
refer to the chat manual page for details.
If your ISP uses PAP or CHAP authentication, you will need to edit the [pap-secrets] or
[chap-secrets] files in [/etc/ppp] directory as well. Refer to the manual pages for these files, as well as
the instruction in the files themselves.
•
The configuration of pppd, the program that maintains the actual connection, is usually contained in
two or three separate files. The first is usually [/etc/ppp/options], which contains options that all of
your system’s PPP connections will use. (Yes, you can have more than one; as many as your computer
has serial ports, generally.)
Here is a sample [/etc/ppp/options] file:
#/etc/ppp/options
asyncmap
0
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