IP获得抓包

抓包验证

[root@baism dhcp]# tcpdump -nn -vvv -s 1500 -i ens33 host 192.168.11.16 and udp port 67 or udp port 68

11:32:41.001286 IP (tos 0x10, ttl 128, id 0, offset 0, flags [none], proto UDP (17), length 328)
0.0.0.0.68 > 255.255.255.255.67: [udp sum ok] BOOTP/DHCP, Request from 00:0c:29:1a:f8:c7, length 300, xid 0x336cb11e, Flags [none] (0x0000)
Client-Ethernet-Address 00:0c:29:1a:f8:c7
Vendor-rfc1048 Extensions
Magic Cookie 0x63825363
DHCP-Message Option 53, length 1: Discover
Requested-IP Option 50, length 4: 192.168.11.252
Parameter-Request Option 55, length 13:
Subnet-Mask, BR, Time-Zone, Classless-Static-Route
Domain-Name, Domain-Name-Server, Hostname, YD
YS, NTP, MTU, Option 119
Default-Gateway
END Option 255, length 0
PAD Option 0, length 0, occurs 35

11:32:41.001569 IP (tos 0x10, ttl 128, id 0, offset 0, flags [none], proto UDP (17), length 330)
192.168.11.16.67 > 192.168.11.252.68: [udp sum ok] BOOTP/DHCP, Reply, length 302, xid 0x336cb11e, Flags [none] (0x0000)
Your-IP 192.168.11.252
Client-Ethernet-Address 00:0c:29:1a:f8:c7
Vendor-rfc1048 Extensions
Magic Cookie 0x63825363
DHCP-Message Option 53, length 1: Offer
Server-ID Option 54, length 4: 192.168.11.16
Lease-Time Option 51, length 4: 7200
Subnet-Mask Option 1, length 4: 255.255.255.0
BR Option 28, length 4: 192.168.11.255
Domain-Name-Server Option 6, length 8: 202.106.0.20,114.114.114.114
Hostname Option 12, length 16: "test.ayitula.com"
Default-Gateway Option 3, length 4: 192.168.11.254
END Option 255, length 0

11:32:41.002920 IP (tos 0x10, ttl 128, id 0, offset 0, flags [none], proto UDP (17), length 328)
0.0.0.0.68 > 255.255.255.255.67: [udp sum ok] BOOTP/DHCP, Request from 00:0c:29:1a:f8:c7, length 300, xid 0x336cb11e, Flags [none] (0x0000)
Client-Ethernet-Address 00:0c:29:1a:f8:c7
Vendor-rfc1048 Extensions
Magic Cookie 0x63825363
DHCP-Message Option 53, length 1: Request
Server-ID Option 54, length 4: 192.168.11.16
Requested-IP Option 50, length 4: 192.168.11.252
Parameter-Request Option 55, length 13:
Subnet-Mask, BR, Time-Zone, Classless-Static-Route
Domain-Name, Domain-Name-Server, Hostname, YD
YS, NTP, MTU, Option 119
Default-Gateway
END Option 255, length 0
PAD Option 0, length 0, occurs 29

11:32:41.003196 IP (tos 0x10, ttl 128, id 0, offset 0, flags [none], proto UDP (17), length 330)
192.168.11.16.67 > 192.168.11.252.68: [udp sum ok] BOOTP/DHCP, Reply, length 302, xid 0x336cb11e, Flags [none] (0x0000)
Your-IP 192.168.11.252
Client-Ethernet-Address 00:0c:29:1a:f8:c7
Vendor-rfc1048 Extensions
Magic Cookie 0x63825363
DHCP-Message Option 53, length 1: ACK
Server-ID Option 54, length 4: 192.168.11.16
Lease-Time Option 51, length 4: 7200
Subnet-Mask Option 1, length 4: 255.255.255.0
BR Option 28, length 4: 192.168.11.255
Domain-Name-Server Option 6, length 8: 202.106.0.20,114.114.114.114
Hostname Option 12, length 16: "test.ayitula.com"
Default-Gateway Option 3, length 4: 192.168.11.254
END Option 255, length 0