229 lines
3.6 KiB
HTML
229 lines
3.6 KiB
HTML
<HTML
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><HEAD
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><TITLE
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>Debugging Your PPP Setup</TITLE
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.57"><LINK
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REL="HOME"
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TITLE="Linux Network Administrators Guide"
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REL="UP"
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TITLE="The Point-to-Point Protocol"
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HREF="x-087-2-ppp.html"><LINK
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REL="PREVIOUS"
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TITLE="Authentication with PPP"
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HREF="x-087-2-ppp.authentication.html"><LINK
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REL="NEXT"
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TITLE="More Advanced PPP Configurations"
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>Linux Network Administrators Guide</TH
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WIDTH="10%"
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>Prev</A
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><TD
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WIDTH="80%"
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ALIGN="center"
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VALIGN="bottom"
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>Chapter 8. The Point-to-Point Protocol</TD
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><TD
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WIDTH="10%"
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><H1
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><A
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NAME="AEN7261"
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>8.9. Debugging Your PPP Setup</A
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></H1
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><P
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>
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By default, <B
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CLASS="COMMAND"
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>pppd</B
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> logs any warnings and error messages
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to <B
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CLASS="COMMAND"
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>syslog</B
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> 's <SPAN
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CLASS="SYSTEMITEM"
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>daemon</SPAN
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>
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facility. You have to add an entry to <TT
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CLASS="FILENAME"
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>syslog.conf</TT
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> that redirects
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these messages to a file or even the console; otherwise, <B
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CLASS="COMMAND"
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>syslog</B
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>
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simply discards them. The following entry
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sends all messages to <TT
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CLASS="FILENAME"
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>/var/log/ppp-log</TT
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>:
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<TABLE
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BORDER="0"
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BGCOLOR="#E0E0E0"
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WIDTH="100%"
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><TR
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><TD
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><PRE
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CLASS="SCREEN"
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>daemon.* /var/log/ppp-log</PRE
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></TD
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></TR
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></TABLE
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></P
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><P
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>If your PPP setup doesn't work right away, you should look in this log
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file. If the log messages don't help, you can also turn on extra
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debugging output using the <TT
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CLASS="OPTION"
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>debug</TT
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> option. This output makes
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<B
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CLASS="COMMAND"
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>pppd</B
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> log the contents of all control packets sent
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or received to <B
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CLASS="COMMAND"
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>syslog</B
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>. All messages then go to the
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<SPAN
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CLASS="SYSTEMITEM"
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>daemon</SPAN
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> facility.</P
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><P
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>
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Finally, the most drastic way to check a problem is to enable kernel-level
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debugging by invoking <B
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CLASS="COMMAND"
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>pppd</B
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> with the <TT
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CLASS="OPTION"
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>kdebug</TT
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>
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option. It is followed by a numeric argument that is the sum of the
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following values: 1 for general debug messages, 2 for printing the contents of
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all incoming HDLC frames, and 4 to make the driver print all outgoing
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HDLC frames. To capture kernel debugging messages, you must either run
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a <B
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CLASS="COMMAND"
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>syslogd</B
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> daemon that reads the
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<TT
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CLASS="FILENAME"
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>/proc/kmsg</TT
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> file, or the <B
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CLASS="COMMAND"
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>klogd</B
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> daemon.
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Either of them directs kernel debugging to the <B
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CLASS="COMMAND"
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>syslog</B
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>
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<SPAN
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CLASS="SYSTEMITEM"
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>kernel</SPAN
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> facility. </P
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></DIV
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><DIV
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ALIGN="left"
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VALIGN="top"
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><A
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HREF="x-087-2-ppp.authentication.html"
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>Prev</A
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></TD
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ALIGN="center"
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VALIGN="top"
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HREF="index.html"
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>Home</A
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VALIGN="top"
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HREF="x7297.html"
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>Next</A
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></TD
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></TR
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><TR
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><TD
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WIDTH="33%"
|
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ALIGN="left"
|
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VALIGN="top"
|
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>Authentication with PPP</TD
|
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><TD
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WIDTH="34%"
|
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ALIGN="center"
|
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VALIGN="top"
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><A
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HREF="x-087-2-ppp.html"
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>Up</A
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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>More Advanced PPP Configurations</TD
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></TR
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></TABLE
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> |