我有两个接口wan0和wg0。路由表如下所示：
::1 dev lo proto kernel metric 256 pref medium
2a0c:xxx:yyy:zz00::/56 dev wg0 proto static metric 20 pref medium
2a0c:xxx::/32 dev wan0 proto kernel metric 256 pref medium
2a0c:xxx::/32 dev wan0 proto ra metric 1024 expires 2591957sec pref medium
fe80::/64 dev wan0 proto kernel metric 256 pref medium
default proto static metric 1024 pref medium
nexthop via 2a0c:xxx::1 dev wan0 weight 1
nexthop via fe80::****:****:****:3780 dev wan0 weight 1
当我尝试dns.google从wg0接口 ping 时，数据包没有重定向到接口wan0。为什么？
接口上的 tcpdumpwg0给出如下信息：
IP6 2a0c:xxx:yyy:zz60::wwww > dns.google: ICMP6, echo request, id 1, seq 5093, length 40
IP6 2a0c:xxx:yyy::1 > 2a0c:xxx:yyy:zz60::wwww: ICMP6, destination unreachable, unreachable address dns.google, length 88
IP6 2a0c:xxx:yyy:zz60::wwww > dns.google: ICMP6, echo request, id 1, seq 5094, length 40
IP6 2a0c:xxx:yyy:zz60::wwww > dns.google: ICMP6, neighbor solicitation, who has dns.google, length 26
IP6 2a0c:xxx:yyy:zz60::wwww > dns.google: ICMP6, neighbor solicitation, who has dns.google, length 26
IP6 2a0c:xxx:yyy:zz60::wwww > dns.google: ICMP6, neighbor solicitation, who has dns.google, length 26
IP6 2a0c:xxx:yyy::1 > 2a0c:xxx:yyy:zz60::wwww: ICMP6, destination unreachable, unreachable address dns.google, length 88
IP6 2a0c:xxx:yyy:zz60::wwww > dns.google: ICMP6, echo request, id 1, seq 5095, length 40
通过 ip -6 r get 检查路由显示正确路由（2001:4860:4860::8888 是 dns.google）：
❯ ip -6 r get to 2001:4860:4860::8888 from 2a0c:xxx:yyy:zz60::wwww iif wg0
2001:4860:4860::8888 from 2a0c:xxx:yyy:zz60::wwww via 2a0c:xxx::1 dev wan0 proto static metric 1024 iif wg0 pref medium
有时数据包仍会被重定向到 wan0 接口，但这种情况很少发生。