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tcpdump and icmp



Dear misc_(_at_)_openbsd_(_dot_)_org,

some questions:

1. why tcpdump's -q doesn't work for ESP and ICMP packets
as expected (only print protocol, packet size and some
flags)?

2. why tcpdump doesn't prints packet size for icmp?

# tcpdump -qni vlan0 tcp
tcpdump: listening on vlan0
15:58:54.100615 x.x.x.x.x > y.y.y.y.y: tcp 300 (DF)
15:58:54.131482 y.y.y.y.y > x.x.x.x.x: tcp 0 (DF)

# tcpdump -qni vlan0 udp
tcpdump: listening on vlan0
15:44:41.435572 x.x.x.x.x > y.y.y.y.y:  udp 25
15:44:41.436159 y.y.y.y.y > x.x.x.x.x:  udp 75

# tcpdump -qni vlan0 icmp
tcpdump: listening on vlan0
15:45:37.136885 x.x.x.x > y.y.y.y: icmp: echo request
15:45:37.136902 y.y.y.y > x.x.x.x: icmp: echo reply

# tcpdump -qni vlan0 esp
tcpdump: listening on vlan0
15:41:23.990390 esp x.x.x.x > y.y.y.y spi 0xXXXXXXXX seq 6499 len 100 (DF) [tos 0x50]
15:41:23.990627 esp y.y.y.y > x.x.x.x spi 0xYYYYYYYY seq 5285 len 100 (DF)

Truly yours
 Alexey E. Suslikov