# tcpdump -nni eth0 udp and port 67 or 68
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes
17:44:46.340824 IP 0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request from 00:15:17:b4:0f:7a, length: 300
17:44:57.340941 IP 0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request from 00:15:17:b4:0f:7a, length: 300

# tcpdump -nni vzbr0 udp and port 67 or 68
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on vzbr0, link-type EN10MB (Ethernet), capture size 96 bytes

0 packets captured
0 packets received by filter
0 packets dropped by kernel