1PPPOE-SNIFF(8) System Manager's Manual PPPOE-SNIFF(8)
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6 pppoe-sniff - examine network for non-standard PPPoE frames
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9 pppoe-sniff [options]
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13 pppoe-sniff listens for likely-looking PPPoE PADR and session frames
14 and deduces extra options required for pppoe(8) to work.
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16 Some DSL providers seem to use non-standard frame types for PPPoE
17 frames, and/or require a certain value in the Service-Name field. It
18 is often easier to sniff those values from a machine which can successâ
19 fully connect rather than try to pry them out of the DSL provider.
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21 To use pppoe-sniff, you need two computers, a DSL modem and an Ethernet
22 hub (not an Ethernet switch.)
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24 If the DSL modem normally connects directly to your computer's Ethernet
25 card, connect it to the "uplink" port on the Ethernet hub. Plug two
26 computers into normal ports on the hub. On one computer, run whatever
27 software the DSL provider gave you on whatever operating system the DSL
28 provider supports. On the other computer, run Linux and log in as
29 root.
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31 On the Linux machine, put the Ethernet interface into promiscuous mode
32 and start pppoe-sniff. If the ethernet interface is eth0, for example,
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35 ifconfig eth0 promisc
36 pppoe-sniff -I eth0
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38 On the other machine, start your DSL connection as usual. After a
39 short time, pppoe-sniff should print recommendations for the value of
40 PPPOE_EXTRA. Set this value in /etc/ppp/pppoe.conf.
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42 After pppoe-sniff finishes (or you stop it if it seems hung), remember
43 to turn off promiscuous mode:
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45 ifconfig eth0 -promisc
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49 -I interface
50 The -I option specifies the Ethernet interface to use. Under
51 Linux, it is typically eth0 or eth1. The interface should be
52 "up" and in promiscuous mode before you start pppoe-sniff.
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55 -V The -V option causes pppoe-sniff to print its version number and
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60 pppoe-sniff only works on Linux.
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64 pppoe-sniff was written by Dianne Skoll <dianne@skoll.ca>.
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66 The pppoe home page is https://dianne.skoll.ca/projects/rp-pppoe/.
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70 pppoe-start(8), pppoe-stop(8), pppoe-connect(8), pppd(8),
71 pppoe.conf(5), pppoe(8), pppoe-setup(8), pppoe-status(8), pppoe-
72 server(8), pppoe-relay(8)
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774th Berkeley Distribution 3 July 2000 PPPOE-SNIFF(8)