非常簡單的問題，是 DNS 不能夠 Resolve 的問題。
進一步 Dig-Into 路由器内，和電腦網絡連接内的 DNS 設定。
問題馬上暴露在陽光底下，
8.8.8.8 和 8.8.4.4 美帝 Google 免費提供的 DNS 正式被共匪封殺掉。
208.67.222.222 和 208.67.220.220 也是由 美帝 OpenDNS 免費提供的 DNS 正式被共匪封殺掉。
解決的辦法很簡單，把那些美帝提供的免費 DNS 轉換成爲 中國電信的 DNS （接受阿爺的規管， Logging of all your DNS resolution Digital Clue 以便在出現問題的時候可以重看 DNS 的Resolution 錄影片段） 就馬上解決了這個小問題, 所以長時間在國内工作和居住，就可以煉就一身非凡的實戰網絡功力
馬上恢復正常的上網。（小菜一碟而已，不消 15分鐘内，已經修理妥當）
但作爲自由慣了的香港同胞，我們怎能夠接受背後有一部 Digital 錄影機，記錄下我們的 DNS Resolution 行爲呢 ？？
因爲我們在國内常常看那些甜網，4-Son Video，髮倫供，生果，狂貓，短髮這些反動資訊，被背後的 DNS Resolution 錄影機監控著，心裏縂不是味兒的，雖然我們沒有什麽的行動，只不過是接收這些阿爺不喜歡的電腦資訊而已。
有沒有 C-Hing 可以介紹一些 在自由世界的 免費 DNS Server 呢 ？？
（最好是美帝的，因爲我現在對香港已經沒有多大信心啦，終有一天，我們的破網翻墻的 VPN Server 要帶去美，加，澳 親友的家裏，才能夠繼續破網翻墻，繼續享受先進西方社會裏，沒有任何政治審查的上網服務）
最好不要像美帝的 Google 和 OpenDNS 那麽巨大，那麽吸引眼球， 因爲這些東西，在目前的政治環境下，見光即死，還是小規模地下運作，但多如螞蟻和蝗蟲，共匪的網絡警察就要投降啦（因爲法不治衆嗎）作者: homeinns 時間: 2012-10-31 13:27
DNS hijacking of Great Firewall of China
Last time, we talked about DNS hijacking, and mentioned using trusted Google DNS or OpenDNS to defeat DNS hijacking.
However, your DNS will still be hijacked by Great Firewall of China if you only use Google DNS or OpenDNS.
Why does this happen?
Background knowledge:
The DNS server use UDP (User Datagram Protocol) 53 port to answer the request from user's computer.
UDP is a simpler message-based connectionless protocol which does not set up a dedicated end-to-end connection, and it's reliable.
The client computer (your computer) will accept the first DNS reply from remote if its data format is correct and ignore other replies.
Suppose you are in China and using Google DNS. You are going to open http://releases.mozilla.org
Your computer tries to get IP address of releases.mozilla.org from 8.8.8.8. This request is detected by IDS (Intrusion Detect System) of GFW, and it returns an error IP to your computer immediately. As we say above, your computer will accept this reply and ignore other replies (the real reply). In this way, this domain (releases.mozilla.org) is hijacked.
Conclusion: Your DNS is still hijacked simply because GFW is in the middle of your computer and the destination DNS server , and it controls the DNS reply.
There are two solutions to defeat the DNS hijacking of GFW:
1. Use VPN & Google DNS together. In this way, your DNS request will be encrypted and can't be detected by GFW.
2. Modify the local host file to ensure the hijacked Domain Name will be resolved locally.
這就是我目前使用的臨時解決辦法，臨時使用中國電信的 DNS 來 Resolve URL，
但最終還是要與國内劃清界線，以免被共匪網絡警察 Log 下 DNS Resolution Digital Clue作者: homeinns 時間: 2012-10-31 14:44
封殺了 Google DNS 和 OpenDNS 還有千千萬萬個 XXXX-DNS,
看你殺到手軟,都絕對沒有可能把所有的螞蟻和蝗蟲殺清光的.
Four Alternative DNS Servers to Improve Surfing Speed Google DNS (因爲太揚，已經被正式封殺）:
Google, about half a year ago, entered the world of DNS servers, to have high-performance servers that use, in order to improve the browsing experience for Google users.
To use Google DNS, use the IP address 8.8.8.8 (primary DNS) and 8.8.4.4 (Secondary DNS).
OpenDNS(因爲太揚，已經被正式封殺） :
Another alternative to your ISP, OpenDNS is a great alternative because it includes several filters which can be configured to block unsafe web sites or explicit content. Ideal for schools and businesses.
To use your server: 208.67.222.222 (Primary DNS) and 208.67.220.220 (Secondary DNS).
Advantage DNS :
Advantage DNS resolves all DNS requests through the UltraDNS Directory Services Platform, thus substantially improves navigation. 156.154.70.1 (Primary DNS) and 156.154.71.1 (Secondary DNS).
ScrubIT :
And the last alternative is ScrubIT, a DNS server that regulates the connection filter disallowing dangerous websites. 67.138.54.100 (Primary DNS) and 207.225.209.66 (Secondary DNS).
Alt. solution, use Ip-mailer-like software. Manually, update client side VPN /Remote server IP config depend on freq. of VPN/Remote host IP change. Normal, HK's ISP, freq. of change client's Dynamic IP is lower.
How to Change DNS Server Settings on Microsoft Windows
The DNS settings on a computer running the Microsoft Windows operating system (OS) are configured in the TCP/IP properties window for the computer. The following example to change DNS server settings is based on the steps required to change the settings on Microsoft Windows 7 OS. They may differ slightly based on the specific version of Windows installed on the computer.
Step 1 – Select the “Start” menu button and click the “Control Panel” icon.
Step 2 – Select the “Network and Internet,” “Network and Sharing Center,” and “Change Adapter” menu options.
Step 3 – Choose the network connection to configure to use the public DNS server. For an Ethernet connection you would right click the “Local Area Connection” menu button and then choose the “Properties” menu option. For a wireless connection, right click the “Wireless Network Connection” and choose the “Properties menu choice. Then, enter a password if prompted or confirm that you want to modify the setting.
Step 4 – Choose the “Networking” menu tab. Then select the “Internet Protocol Version 4 (TCP/IPv4) or Internet Protocol Version 6 (TCP/IPv6) menu option followed by clicking the “Properties” menu button.
Step 5 – Select the “Advanced’ menu option and then click the “DNS” menu tab. Note any DNS server IP addresses listed on this screen for future reference and clear from the window. Click the “Ok” menu button.
Step 6 – Chose the “Use the Following DNS Server Addresses” menu options. If you see any addresses listed here write them down. Then, enter the public DNS server addresses in the appropriate window. If you intend on using the Google Public DNS server your entries would be:
Step 7 – Restart the network connection selected earlier for configuration. Then, repeat the steps for any additional network connections that require reconfiguration.作者: dreamy2k 時間: 2013-3-4 10:46
其實有無考慮在家起一個DNS SERVER，起了真的可以解決DNS宣染的問題!!我系家起了只要VPN時派DNS時比返家里的DNS SERVER IP ADDRESS就可以作者: 雯雯 時間: 2013-3-4 11:51
怪不得我29号晚上突然就上不了facebook ，但是youtube还是能上，原来是DNS被封了
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