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Webサイトへのアクセス中にDNSルックアップが失敗するプロキシエラー

こちらが今日の朝までの状況ですが、すべてうまくいきました。過去6か月から、私のドメインの多くは次のようにアクセスできます。

http://site1.myserver.com
http://site2.myserver.com
http://site3.myserver.com
http://site4.myserver.com

これらはすべてリバースプロキシ構成でした。私はそれらのそれぞれにいくつかのアプリケーションを持っています。

今日の朝まで何人かの人々が私にそれを報告しました
http://site1.myserver.com/app1 は機能していませんが、 http://site1.myserver.com はアクセス可能です
しかし http://site2.myserver.com はアクセス可能です
しかし http://site3.myserver.com アクセス可能
しかし http://site4.myserver.comnotアクセス可能

過去6か月間に、これらのApache構成を変更していません
（物事は完璧に機能していたので）

ブラウザに表示されるエラーは、アクセス中に発生します http://site1.myserver.com/app1

Proxy Error

The proxy server received an invalid response from an upstream server.
The proxy server could not handle the request GET /app1.

Reason: DNS lookup failure for: myserver.com

http://site4.myserver.com のエラーも同じです。

だから私は何をチェックインすればいいのでしょうか？

    192.168.1.25 - - [10/Jan/2011:14:50:48 +0530] "GET /app1 HTTP/1.1" 502 531 "-" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.3) Gecko/20100401 Firefox/3.6.3"

Mon Jan 10 14:27:42 2011] [error] (113)No route to Host: proxy: HTTP: attempt to connect to 192.168.1.3:80 (192.168.1.3) failed
[Mon Jan 10 14:27:42 2011] [error] ap_proxy_connect_backend disabling worker for (192.168.1.3)
[Mon Jan 10 14:27:44 2011] [error] proxy: HTTP: disabled connection for (192.168.1.3)
[Mon Jan 10 14:27:44 2011] [error] proxy: HTTP: disabled connection for (192.168.1.3)
[Mon Jan 10 14:27:44 2011] [error] proxy: HTTP: disabled connection for (192.168.1.3)
[Mon Jan 10 14:27:45 2011] [error] proxy: HTTP: disabled connection for (192.168.1.3)
[Mon Jan 10 14:27:45 2011] [error] proxy: HTTP: disabled connection for (192.168.1.3)
[Mon Jan 10 14:27:45 2011] [error] proxy: HTTP: disabled connection for (192.168.1.3)
[Mon Jan 10 14:27:45 2011] [error] proxy: HTTP: disabled connection for (192.168.1.3)
[Mon Jan 10 14:27:46 2011] [error] proxy: HTTP: disabled connection for (192.168.1.3)
[Mon Jan 10 14:27:47 2011] [error] proxy: HTTP: disabled connection for (192.168.1.3)
[Mon Jan 10 14:27:48 2011] [error] proxy: HTTP: disabled connection for (192.168.1.3)
[Mon Jan 10 14:27:48 2011] [error] proxy: HTTP: disabled connection for (192.168.1.3)
[Mon Jan 10 14:27:48 2011] [error] proxy: HTTP: disabled connection for (192.168.1.3)
[Mon Jan 10 14:35:29 2011] [error] [client 192.168.1.25] proxy: DNS lookup failure for: myserver.com returned by /app1
[Mon Jan 10 14:35:30 2011] [error] [client 192.168.1.25] proxy: DNS lookup failure for: myserver.com returned by /app1
[Mon Jan 10 14:35:30 2011] [error] [client 192.168.1.25] proxy: DNS lookup failure for: myserver.com returned by /app1
[Mon Jan 10 14:50:30 2011] [error] [client 192.168.1.25] proxy: DNS lookup failure for: myserver.com returned by /app1
[Mon Jan 10 14:50:48 2011] [error] [client 192.168.1.25] proxy: DNS lookup failure for: myserver.com returned by /app1

およびsite4.myserver.comの場合

私は得る

[Mon Jan 10 14:57:40 2011] [error] [client 192.168.1.25] proxy: DNS lookup failure for: site4.myserver.com returned by /favicon.ico
[Mon Jan 10 14:57:40 2011] [error] [client 192.168.1.25] proxy: DNS lookup failure for: site4.myserver.com returned by /favicon.ico
[Mon Jan 10 14:57:43 2011] [error] [client 192.168.1.25] proxy: DNS lookup failure for: site4.myserver.com returned by /favicon.ico
[Mon Jan 10 15:02:38 2011] [error] [client <some external IP>] proxy: DNS lookup failure for: site4.myserver.com returned by /
[Mon Jan 10 15:03:04 2011] [error] [client <some external IP>] proxy: DNS lookup failure for: site4.myserver.com returned by /, referer: http://site4.myserver.com/
[Mon Jan 10 15:03:04 2011] [error] [client <some external IP>] proxy: DNS lookup failure for: site4.myserver.com returned by /favicon.ico
[Mon Jan 10 15:03:08 2011] [error] [client <some external IP>] proxy: DNS lookup failure for: site4.myserver.com returned by /, referer: http://site4.myserver.com/
[Mon Jan 10 15:03:08 2011] [error] [client <some external IP>] proxy: DNS lookup failure for: site4.myserver.com returned by /favicon.ico
[Mon Jan 10 15:03:10 2011] [error] [client <some external IP>] proxy: DNS lookup failure for: site4.myserver.com returned by /, referer: http://site4.myserver.com/
[Mon Jan 10 15:06:21 2011] [error] [client 192.168.1.25] proxy: DNS lookup failure for: site4.myserver.com returned by /
[Mon Jan 10 15:06:31 2011] [error] [client 192.168.1.25] proxy: DNS lookup failure for: site4.myserver.com returned by /, referer: http://site4.myserver.com/
[Mon Jan 10 15:26:03 2011] [error] [client 192.168.1.25] proxy: DNS lookup failure for: site4.myserver.com returned by /
apache-2.2ubuntureverse-proxylinux
2
Bond

この問題は、prodnsとdnsproxyをインストールすることで解決しました。

1
Bond

あなたが何も変更していない場合は、他の何かが明らかに変更されています。

リバースプロキシサーバーからDNS解決を確認する必要があります。

プロキシが指しているDNSサーバーにキャッシュされた否定的な応答があるようです。

1
Essobi