https://www.cnblogs.com/bass6/p/5819928.html
介绍的比较全，我能看懂还
[root@bass Desktop]# tcpdump -i eth0 -w dump.pcap -i #是指定要抓取的网卡 -w #指定结果保存的位置 [root@bass Desktop]# tcpdump -i eth0 -w dump.pcap -v tcpdump: WARNING: eth0: no IPv4 address assigned tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes ^C189 packets captured 189 packets received by filter 0 packets dropped by kernel －v＃主要是为了得到Got 15这个数，当想要停止的时候，按下ctrl + c [root@bass Desktop]# ll -h dump.pcap -rw-r--r--. 1 tcpdump tcpdump 18K Aug 30 13:19 dump.pcap
然后用xshell ftp下载包