Can tcpdump monitor the ppp interface?

Can tcpdump monitor the ppp interface?

Post by Al Longye » Sat, 14 Jan 1995 11:51:49

>I've compiled the latest tcpdump, and enabled what I thought was support
>for PPP.  When I try to use it, however, I get:
>fire~# tcpdump -i ppp0
>tcpdump: snoop: unknown physical layer type
>Is there a way to fix this?


Quote:>Am I missing something obvious?

Did you apply the two patches to the version 3.0 code? Both patches
are on

In addition, you should use the "-p" flag to prevent the
point-to-point devices from trying promisc mode.

The tcpdump program will monitor the IP protocol since it is only this
protocol which will go through the hooks for tcpdump. The PPP protocol
suite for LCP, CHAP, PAP and IPCP are traced using the 'debug' mode.



1. Using tcpdump to monitor remote network interface traffic


I would like to ask if tcpdump being used to monitor traffic to & from
an LAN interface, does tcpdump need to run at a host in the same
subnet as the interface being monitored ? Any tcpdump software
available for monitoring traffic to & from LAN interface at different
subnet ?

2. Redhat Linux 5 and SML-NJ 0.93

3. Need tcpdump-like utility for PPP interface.

4. commercial tools for DNS mgmt?

5. tcpdump 3.0 with ppp interface

6. Problems compiling Pcomm1.2 (Linker error)

7. Router dropping packets from eth interface to ppp interface

8. SCSI Problem - Please Help

9. Build Route between PPP Interface/Ethernet Interface

10. tcpdump and aix and SP switch interface

11. tcpdump seeing aliased interfaces?

12. tcpdump doesn't work an all interfaces

13. tcpdump monitor token ring?