Tcpdump is great and I was looking ahead using it. The bigger was my surprise when I could not, because tcpdump does not recognize my PPP internet connection (or better the ppp0 device) as being configured. Apple's Network Utility has the same sort of problem (it shows only en0, even while being on-line via PPP). Here's an example:
root# ifconfig ppp0Please help - how can I get packet monitoring on PPP working??
ppp0: flags=8055 mtu 1500
inet 62.84.136.53 --> 62.84.128.250 netmask 0xff000000
root# tcpdump -i ppp0
tcpdump: ppp0: Device not configured
root#
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