我在与 VPN 服务器建立连接时遇到了一些问题。这是相关主题的链接：StackExchange VPN 连接。
主要是 DNS 问题，现在可以了。但是，我现在可以解析一些名称，但不是全部。我可以解决www.google.com，但不是torrent.ubuntu.com例如。即使我使用命令指定要使用的 DNS，在连接到 VPN 时dig也无法解析。torrent.ubuntu.com当我没有连接VPN时，我可以解析它，也可以使用我的VPN服务器的DNS来解析它。
未连接到 VPN（84.200.69.80 是我的 VPN 服务器给出的 DNS 地址）：
pi@raspberrypi:/etc/openvpn/vpnbook $ dig torrent.ubuntu.com
; <<>> DiG 9.9.5-9+deb8u10-Raspbian <<>> torrent.ubuntu.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 12612
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;torrent.ubuntu.com. IN A
;; ANSWER SECTION:
torrent.ubuntu.com. 600 IN A 91.189.95.21
;; Query time: 26 msec
;; SERVER: 194.168.4.100#53(194.168.4.100)
;; WHEN: Tue Mar 28 23:36:14 UTC 2017
;; MSG SIZE rcvd: 63
pi@raspberrypi:/etc/openvpn/vpnbook $ dig @8.8.8.8 torrent.ubuntu.com
; <<>> DiG 9.9.5-9+deb8u10-Raspbian <<>> @8.8.8.8 torrent.ubuntu.com
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 54658
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;torrent.ubuntu.com. IN A
;; ANSWER SECTION:
torrent.ubuntu.com. 565 IN A 91.189.95.21
;; Query time: 38 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Tue Mar 28 23:36:30 UTC 2017
;; MSG SIZE rcvd: 63
pi@raspberrypi:/etc/openvpn/vpnbook $ dig @84.200.69.80 torrent.ubuntu.com
; <<>> DiG 9.9.5-9+deb8u10-Raspbian <<>> @84.200.69.80 torrent.ubuntu.com
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 25789
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 4, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;torrent.ubuntu.com. IN A
;; ANSWER SECTION:
torrent.ubuntu.com. 153 IN A 91.189.95.21
;; AUTHORITY SECTION:
ubuntu.com. 600 IN NS ns4.p27.dynect.net.
ubuntu.com. 600 IN NS ns2.p27.dynect.net.
ubuntu.com. 600 IN NS ns1.p27.dynect.net.
ubuntu.com. 600 IN NS ns3.p27.dynect.net.
;; Query time: 48 msec
;; SERVER: 84.200.69.80#53(84.200.69.80)
;; WHEN: Tue Mar 28 23:36:47 UTC 2017
;; MSG SIZE rcvd: 149
连接到 VPN：
pi@raspberrypi:/etc/openvpn/vpnbook $ dig torrent.ubuntu.com
; <<>> DiG 9.9.5-9+deb8u10-Raspbian <<>> torrent.ubuntu.com
;; global options: +cmd
;; connection timed out; no servers could be reached
pi@raspberrypi:/etc/openvpn/vpnbook $ dig @84.200.69.80 torrent.ubuntu.com
; <<>> DiG 9.9.5-9+deb8u10-Raspbian <<>> @84.200.69.80 torrent.ubuntu.com
; (1 server found)
;; global options: +cmd
;; connection timed out; no servers could be reached
pi@raspberrypi:/etc/openvpn/vpnbook $ dig @8.8.8.8 torrent.ubuntu.com
; <<>> DiG 9.9.5-9+deb8u10-Raspbian <<>> @8.8.8.8 torrent.ubuntu.com
; (1 server found)
;; global options: +cmd
;; connection timed out; no servers could be reached
pi@raspberrypi:/etc/openvpn/vpnbook $ dig www.google.com
; <<>> DiG 9.9.5-9+deb8u10-Raspbian <<>> www.google.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 59828
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;www.google.com. IN A
;; ANSWER SECTION:
www.google.com. 132 IN A 172.217.20.196
;; Query time: 211 msec
;; SERVER: 84.200.69.80#53(84.200.69.80)
;; WHEN: Tue Mar 28 23:38:58 UTC 2017
;; MSG SIZE rcvd: 59
答案1
在互联网上浏览了一下后，很明显 VPN 服务器正在阻止每个包含“torrent”一词的 DNS 请求，即使它是像 .torrent 这样的合法 torrent torrent.ubuntu.com。