15:05:43.356015 IP gateway.domain > localhost.localdomain.45436: 24484 2/1/0 CNAME images0.cnblogs.com.cdn.dnsv1.com., CNAME 1069954.p23.tc.cdntip.com. (174) 10 packets captured 13 packets received by filter 0 packets dropped by kernel 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11....
这样,数据经过本地TCP层分段后,交给本地IP层,在本地IP层就不需要分片了。但是在下一跳路由(Next Hop)的邻居路由器上可能发生IP分片!因为路由器的网卡的MTU可能小于需要转发的IP数据报的大小。 这时候,在路由器上可能发生两种情况: (1)如果源发送端设置了这个IP数据包可以分片(May Fragment,DF=0),路由器将IP...
man pcap-filter 高级过滤方式 了解如何从包头过滤信息 proto[x:y] : 过滤从x字节开始的y字节数。比如ip[2:2]过滤出3、4字节(第一字节从0开始排) proto[x:y] & z = 0 : proto[x:y]和z的与操作为0 proto[x:y] & z !=0 : proto[x:y]和z的与操作不为0 proto[x:y] & z = z : proto...
filter 是过滤包的条件,举例:tcp,portrange 1-1000,src port 58895,hostwww.itshouce.com.cn, filter可以进行组合 比如:dst port 3306 and src port 58895,portrange 1-1000 or src port 58895 not dst port 3306 option filter 举例:tcpdump -i any -n portrange 1-3306 or portrange 10000-58895 tcpd...
1 packets received by filter 0 packets dropped by kernel 在此,我重点解释下这个命令: -i选项: 是interface的含义,是指我们有义务告诉tcpdump希望他去监听哪一个网卡。这在我们一台服务器有多块网卡时很有必要。 -nn选项: 意思是说当tcpdump遇到协议号或端口号时,不要将这些号码转换成对应的协议名称或端口...
man pcap-filter 1、只抓取UDP数据包 [root@localhost~]# tcpdump-i ens5f1-c2'udp'tcpdump:verbose output suppressed,use-v or-vvforfull protocol decode listening on ens5f1,link-type EN10MB(Ethernet),capture size262144bytes14:37:38.852304IPgateway.35428>239.255.255.250.ssdp:UDP,length39514:37:38.8...
Linux Tcpdump: Filter ipv6 ntp ping packets Tcpdump: capture DHCP & DHCPv6 packets 20 Advanced Tcpdump Examples On Linux 10 Useful tcpdump command examples TCPDUMP README Tcpdump is one of the best network analysis-tools ever for information security professionals. ...
If you are typing such a filter on the UNIX command line, the backslash is special for UNIX shells, so the backslash must be escaped with another backslash. Sign in to download full-size image This example captures all packets in their entirety for destination IP 192.168.1.1 going to and ...
IP地址 TCP(UDP)端口 HTTP Host/URI等 IP序列号 TCP序列号 3.IP 头部 4.UDP 头部 Tips:Destination Port表示目的端口,Source Port表示消息来源端口(回送消息也是依据此端口),Checksum表示防止错误的校验码。 5.TCP 协议的任务 主机内的进程寻址 创建、管理、终止连接 ...
tcpdumpallows you to specify network packets that are either using some portXas source or destination. For example, to capture DNS traffic, you can useport 53. You could prefix theportkeyword withsrc/dstassrc port 53ordst port 53and filter it even further. ...