Re: tlug: PPP&RH5.0 (was: Infoworld Review)

["A.Tomita,Jr." <alberto@example.com>]

Does anybody know what a "PPP frame with bad fcs" is ?

I'm starting to suspect that the problem with my machine may
not be related to the routing table after all. I watched the
packets going thru ppp0 with "tcpdump -i ppp0 -n" while
pinging a machine outside and got:

02:28:36.193011 165.76.88.78 > 133.34.19.33: icmp: echo request
02:28:37.193011 165.76.88.78 > 133.34.19.33: icmp: echo request
02:28:38.193011 165.76.88.78 > 133.34.19.33: icmp: echo request
02:28:39.193011 165.76.88.78 > 133.34.19.33: icmp: echo request

So, I suspect the problem is between 165.76.88.78 (that's the
machine's local PPP assigned address) and the other end of the
PPP link. Raising the pppd debug level, I found these "bad fcs" 
errors that were registered in /var/log/messages with exactly the
same time stamp. Just a coincidence?

Feb  4 02:26:35 neutron pppd[544]: Serial connection established.
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set flags to 10000
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set flags to 10000
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set xasyncmap
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set xmit asyncmap ffffffff
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set flags to 10000
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set mru to 5dc
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set rcv asyncmap ffffffff
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set flags to 10000
Feb  4 02:26:36 neutron pppd[544]: Using interface ppp0
Feb  4 02:26:36 neutron pppd[544]: Connect: ppp0 <--> /dev/modem
Feb  4 02:26:36 neutron kernel: ppp: successfully queued 10 bytes, flags =
f0100
00
Feb  4 02:26:36 neutron kernel: ppp: successfully queued 20 bytes, flags =
f0100
00
Feb  4 02:26:36 neutron kernel: ppp: successfully queued 12 bytes, flags =
f0100
00
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set xmit asyncmap 0
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set flags to f010000
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set mru to 5dc
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set rcv asyncmap ffffffff
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set flags to f010010
Feb  4 02:26:36 neutron kernel: ppp: successfully queued 14 bytes, flags =
f0100
10
Feb  4 02:26:36 neutron pppd[544]: Remote message: Welcome
Feb  4 02:26:36 neutron pppd[544]: local  IP address 165.76.88.78
Feb  4 02:26:36 neutron pppd[544]: remote IP address 165.76.88.30
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set flags to f010050
Feb  4 02:26:36 neutron kernel: ppp: successfully queued 11 bytes, flags =
f0100
50
Feb  4 02:26:36 neutron kernel: ppp: successfully queued 18 bytes, flags =
f0100
50
Feb  4 02:26:36 neutron kernel: ppp: successfully queued 12 bytes, flags =
f0100
50
Feb  4 02:26:36 neutron kernel: ppp: successfully queued 6 bytes, flags =
f01005
0
Feb  4 02:26:36 neutron kernel: ppp: successfully queued 12 bytes, flags =
f0100
50
Feb  4 02:26:36 neutron kernel: ppp: successfully queued 18 bytes, flags =
f0100
50
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set maxcid to 16
Feb  4 02:26:36 neutron kernel: ppp_tty_ioctl: set flags to f010054
Feb  4 02:26:36 neutron kernel: ppp: channel ppp0 going up for IP packets!
Feb  4 02:26:36 neutron kernel: ppp: successfully queued 6 bytes, flags =
f01005
4
Feb  4 02:28:23 neutron kernel: ppp: channel ppp0 mtu = 1524, mru = 1500
Feb  4 02:28:29 neutron kernel: ppp: frame with bad fcs, excess = b819
Feb  4 02:28:34 neutron kernel: ppp: frame with bad fcs, excess = d873
Feb  4 02:28:35 neutron kernel: ppp: frame with bad fcs, excess = 22b5
Feb  4 02:28:36 neutron kernel: ppp: frame with bad fcs, excess = dbd6
Feb  4 02:28:37 neutron kernel: ppp: frame with bad fcs, excess = d508
Feb  4 02:28:38 neutron kernel: ppp: frame with bad fcs, excess = 72f8
Feb  4 02:28:39 neutron kernel: ppp: frame with bad fcs, excess = 2a38
Feb  4 02:28:40 neutron kernel: ppp: frame with bad fcs, excess = 257f
Feb  4 02:28:41 neutron kernel: ppp: frame with bad fcs, excess = 281c
Feb  4 02:28:42 neutron kernel: ppp: frame with bad fcs, excess = 4411
Feb  4 02:28:43 neutron kernel: ppp: frame with bad fcs, excess = 1cc1
Feb  4 02:28:44 neutron kernel: ppp: frame with bad fcs, excess = 9d0c
Feb  4 02:28:45 neutron kernel: ppp: frame with bad fcs, excess = acd0
Feb  4 02:28:46 neutron kernel: ppp: frame with bad fcs, excess = 12cf
Feb  4 02:28:47 neutron kernel: ppp: frame with bad fcs, excess = 72e9
Feb  4 02:28:48 neutron kernel: ppp: frame with bad fcs, excess = 9149
Feb  4 02:28:48 neutron kernel: ppp: frame with bad fcs, excess = bb08
Feb  4 02:28:49 neutron kernel: ppp: frame with bad fcs, excess = 3d1a
Feb  4 02:28:50 neutron kernel: ppp: frame with bad fcs, excess = 54d0

---
A.Tomita,Jr.   atomita@example.com
               atomita@example.com

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