[NS]freebsd 7.0 could not send Neighbor Solicitation when I reboot the freebsd

[wang_jiabo]

Hello, everyone:
 when I reboot freebsd7.0, it did not send NS package, I only can 
receive RS.
could you tell me why.
  tcpdump log info:
       reading from file 1.2.A, link-type EN10MB (Ethernet)
13:20:11.994102 IP6 fe80::2e0:4cff:fe19:129f > ff02::2: ICMP6, router 
solicitation, length 16
13:20:11.994107 IP6 fe80::2e0:4cff:fe19:129f > ff02::2: ICMP6, router 
solicitation, length 16
13:20:14.546713 IP6 fe80::2e0:4cff:fe19:129f > ff02::2:fc25:dbcf: HBH 
ICMP6, multicast listener reportmax resp delay: 0 addr: 
ff02::2:fc25:dbcf, length 24
13:20:14.546725 IP6 fe80::2e0:4cff:fe19:129f > ff02::2:fc25:dbcf: HBH 
ICMP6, multicast listener reportmax resp delay: 0 addr: 
ff02::2:fc25:dbcf, length 24
13:20:15.546584 IP6 fe80::2e0:4cff:fe19:129f > ff02::1:ff19:129f: HBH 
ICMP6, multicast listener reportmax resp delay: 0 addr: 
ff02::1:ff19:129f, length 24
13:20:15.546595 IP6 fe80::2e0:4cff:fe19:129f > ff02::1:ff19:129f: HBH 
ICMP6, multicast listener reportmax resp delay: 0 addr: 
ff02::1:ff19:129f, length 24
13:20:15.993560 IP6 fe80::2e0:4cff:fe19:129f > ff02::2: ICMP6, router 
solicitation, length 16
13:20:15.993567 IP6 fe80::2e0:4cff:fe19:129f > ff02::2: ICMP6, router 
solicitation, length 16
13:20:19.994014 IP6 fe80::2e0:4cff:fe19:129f > ff02::2: ICMP6, router 
solicitation, length 16
13:20:19.994021 IP6 fe80::2e0:4cff:fe19:129f > ff02::2: ICMP6, router 
solicitation, length 16