tcpdump -A -s0 tcp dst port 80
…忘记了-s 参数 记录一下。。
-s Snarf snaplen bytes of data from each packet rather than the default of 68 (with SunOS’s NIT, the minimum is actually 96). 68 bytes is ade-
quate for IP, ICMP, TCP and UDP but may truncate protocol information from name server and NFS packets (see below). Packets truncated
because of a limited snapshot are indicated in the output with ‘‘[|proto]’’, where proto is the name of the protocol level at which the
truncation has occurred. Note that taking larger snapshots both increases the amount of time it takes to process packets and, effectively,
decreases the amount of packet buffering. This may cause packets to be lost. You should limit snaplen to the smallest number that will
capture the protocol information you’re interested in. Setting snaplen to 0 means use the required length to catch whole packets.