Hey James - thanks for the input, Starting over at top :-) Trying to find out why the capture file does not show up. I am interested in the parts which tshark does not display. https://wiki.wireshark.org/CaptureSetup/PPP#Linux I activated "debug" and "kdebug 4" to track down probable causes for the missing capture file (well yes, kdebug may not make much sense). I have to admit that I went the lazy way and did not compile pppd myself yet. ----- Original Message ----- *From:* James Carlson *To:* Thomas Bergholz, Problems With Pppd Option: Record File *CC:* *Sent:* Wed, 18 Nov 2015 14:42:41 -0500 *Subject:* Re: Problems with pppd option: record file > On 11/18/15 13:13, Thomas Bergholz wrote: >> kdebug 4 > kdebug almost never does what you want, unless you're hacking the kernel > modules themselves. Are you sure you need this? > >> record /tmp/pppd_capture.pcap > This looks to me like a bad idea. First of all, the "record" option, > besides being quite brutal (it uses a pty pair and passes all data back > and forth in and out of the kernel multiple times), does not create pcap > format files. It creates async data files in a special format that only > pppdump normally reads. It's very hard to use, and is definitely NOT an > accurate recording if you're using anything other than PPP on an > asynchronous line. Even then, it's appropriate only if you're debugging > a problem in AHDLC encoding or flow control or something like that. > It's close to worthless for higher level (PPP negotiation or IP data) > debugging. > > And this isn't configured as PPP on an asynchronous line. So, even if > you could make it work, it wouldn't give you accurate results for > debugging, because it passes the data through an asynchronous > pseudo-terminal, and Ethernet is anything but that. > > I suggest just running wireshark on eth0 instead. Since this is a PPPoE > connection, that will capture everything, and wireshark is great at > decoding PPPoE (and PPP) negotiation. > >> unit 0 > Not sure why this appears here. > >> I recongnized that the raspi prints "unrecognized option 'record'", even >> though the "record file" option is mentioned in the pppd manpage. >> Ubuntu does not print this message. > Is this a copy of pppd that you compiled from source or one that you got > from someone else? > > If it's one that you compiled from source, I'd suggest looking at > pppd/tty.c to see why that option is missing. > > If it's one that you got from someone else, then you need to ask them > what's been done to it. Some distributors make changes, and it's > possible they just removed this (mostly useless) option. > > I suggest starting over at the top: what problem are you trying to solve? > -- To unsubscribe from this list: send the line "unsubscribe linux-ppp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
