我的“家庭”网络出了问题……我已经绞尽脑汁了一整天，但仍然找不到解决方案。更糟糕的是，我真的无法确定问题的根源 ;(
我有 3 个子网，配置在 3 个不同的服务器上，位于不同的位置：
10.123.45.0/24 - 位置 A
$ ip route list
default via _PUBLIC_IP_ dev enp7s1 metric 2
10.0.0.0/24 via 10.123.50.5 dev tun0
10.123.45.0/24 dev br0 proto kernel scope link src 10.123.45.1
10.123.50.0/24 via 10.123.50.5 dev tun0
10.123.50.5 dev tun0 proto kernel scope link src 10.123.50.6
_PUBLIC_NETWORK_ dev enp7s1 proto kernel scope link src _PUBLICK_GW_ metric 2
127.0.0.0/8 dev lo scope host
$ sudo ifconfig tun0
tun0: flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST> mtu 1500
inet 10.123.50.6 netmask 255.255.255.255 destination 10.123.50.5
unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 txqueuelen 100 (UNSPEC)
RX packets 58491 bytes 33386378 (31.8 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 68994 bytes 33653956 (32.0 MiB)
TX errors 0 dropped 28 overruns 0 carrier 0 collisions 0
10.123.50.0/24 - VPS - OpenVPN 服务器
$ ip route list
default via _PUBLIC_IP_ dev eth0
10.0.0.0/24 via 10.123.50.2 dev tun0
10.123.45.0/24 via 10.123.50.2 dev tun0
10.123.50.0/24 via 10.123.50.2 dev tun0
10.123.50.2 dev tun0 proto kernel scope link src 10.123.50.1
_PUBLIC_NETWORK_ dev eth0 proto kernel scope link src _PUBLIC_GW_
$ ifconfig tun0
tun0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet addr:10.123.50.1 P-t-P:10.123.50.2 Mask:255.255.255.255
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1
RX packets:307740 errors:0 dropped:0 overruns:0 frame:0
TX packets:309435 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:20958272 (19.9 MiB) TX bytes:66356464 (63.2 MiB)
10.0.0.0/24 - 位置 B
$ ip route list
default via _PUBLIC_IP_ dev eth0
10.0.0.0/24 dev br0 proto kernel scope link src 10.0.0.1
10.123.45.0/24 via 10.123.50.9 dev tun0
10.123.50.0/24 via 10.123.50.9 dev tun0
10.123.50.9 dev tun0 proto kernel scope link src 10.123.50.10
169.254.0.0/16 dev eth0 scope link metric 1000
_PUBLIC_NETWORK_ dev eth0 proto kernel scope link src _PUBLIC_GW_
$ ifconfig tun0
tun0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet addr:10.123.50.10 P-t-P:10.123.50.9 Mask:255.255.255.255
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1
RX packets:37791 errors:0 dropped:0 overruns:0 frame:0
TX packets:37122 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:7688111 (7.3 MiB) TX bytes:2624779 (2.5 MiB)
由于某种原因，我无法从 VPS - OpenVPN 服务器和位置 A 访问 IP > 10.0.0.10 的主机
$ ping 10.0.0.12
PING 10.0.0.12 (10.0.0.12) 56(84) bytes of data.
--- 10.0.0.12 ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 1999ms
从位置 A 执行 ping 操作可使所有 IP <= 10.0.0.10 的主机正常运行。从位置 B 的服务器执行 ping 操作可使所有 10.0.0.x 中的主机正常运行。
$ ping 10.0.0.10
PING 10.0.0.10 (10.0.0.10) 56(84) bytes of data.
64 bytes from 10.0.0.10: icmp_seq=1 ttl=62 time=59.2 ms
64 bytes from 10.0.0.10: icmp_seq=2 ttl=62 time=56.9 ms
64 bytes from 10.0.0.10: icmp_seq=3 ttl=62 time=57.3 ms
--- 10.0.0.10 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2002ms
rtt min/avg/max/mdev = 56.998/57.861/59.230/0.998 ms
当我从位置 B 和 VPS ping 到 A 时，它对所有主机都有效
$ ping 10.123.45.132
PING 10.123.45.132 (10.123.45.132) 56(84) bytes of data.
64 bytes from 10.123.45.132: icmp_seq=1 ttl=63 time=461 ms
64 bytes from 10.123.45.132: icmp_seq=2 ttl=63 time=252 ms
64 bytes from 10.123.45.132: icmp_seq=3 ttl=63 time=416 ms
...
从 tcpdump 角度来看，位置 B 的服务器上发生了以下情况：
$ tcpdump -i br0 src 10.0.0.11 or dst 10.0.0.11 -vv
当我从位置 B 网络 10.0.0.0/24 ping 时，在这种情况下从 10.0.0.1 ping 10.0.0.11
nostromo > 10.0.0.11: ICMP echo request, id 19025, seq 1, length 64
21:52:56.910174 IP (tos 0x0, ttl 64, id 16522, offset 0, flags [none], proto ICMP (1), length 84)
10.0.0.11 > nostromo: ICMP echo reply, id 19025, seq 1, length 64
21:52:57.908878 IP (tos 0x0, ttl 64, id 2419, offset 0, flags [DF], proto ICMP (1), length 84)
nostromo > 10.0.0.11: ICMP echo request, id 19025, seq 2, length 64
21:52:57.909110 IP (tos 0x0, ttl 64, id 16523, offset 0, flags [none], proto ICMP (1), length 84)
10.0.0.11 > nostromo: ICMP echo reply, id 19025, seq 2, length 64
21:52:58.907874 IP (tos 0x0, ttl 64, id 2543, offset 0, flags [DF], proto ICMP (1), length 84)
nostromo > 10.0.0.11: ICMP echo request, id 19025, seq 3, length 64
没关系，我收到了回复
当我在 tcpdump 中从位置 A 10.123.45.0/25 网络 ping 时，我得到：
10.123.45.2 > 10.0.0.11: ICMP echo request, id 8621, seq 17, length 64
21:52:14.645318 IP (tos 0x0, ttl 62, id 2554, offset 0, flags [DF], proto ICMP (1), length 84)
10.123.45.2 > 10.0.0.11: ICMP echo request, id 8621, seq 18, length 64
21:52:15.643949 IP (tos 0x0, ttl 62, id 3048, offset 0, flags [DF], proto ICMP (1), length 84)
10.123.45.2 > 10.0.0.11: ICMP echo request, id 8621, seq 19, length 64
没有回应，但是为什么???
桥梁配置：
地点 A:
bridge_br0="enp5s0"
config_br0="10.123.45.1/24"
brctl_br0="setfd 0 sethello 10 stp off"
地点 B：
auto br0
iface br0 inet static
bridge_ports eth1
bridge_stp off
bridge_waitport 0
bridge_fd 0
address 10.0.0.1
netmask 255.255.255.0
broadcast 10.0.0.255
我依靠您的智慧，请帮忙。