我昨天在 stackoverflow 上发布了一个问题这里但我认为这可能与服务器有关。我使用 PHP curl 功能连接到服务器，然后生成 PDF 文件并将其发送回来，我只在第一次执行脚本时收到错误，再次执行时一切正常。有关更多详细信息，请查看 stackoverflow 上的问题。
我收到了这条消息
* About to connect() to 196.41.139.168 port 80 (#0)
* Trying 196.x.x.x... * connected
* Connected to 196.x.x.x (196.x.x.x) port 80 (#0)
> POST /serve/?r=pdf/generatePdf HTTP/1.1
Host: 196.x.x.x
Accept: */*
Content-Length: 7115
Content-Type: application/x-www-form-urlencoded
Expect: 100-continue
* Recv failure: Connection reset by peer
* Closing connection #0
012 20:23:49 GMT
< Server: Apache/2.2.15 (CentOS)
< X-Powered-By: PHP/5.3.3
< Connection: close
< Transfer-Encoding: chunked
< Content-Type: text/html; charset=UTF-8
<
* Closing connection #0
现在我在 serverfault 上问这个问题是为了查明服务器上是否可能需要设置一个设置，它是一台运行 CENTOS 6 的 VPS，安装了 WKHTML2PDF、LAMP 和 CURL。我可以获得解决这个问题所需的任何信息。。我没什么主意了。
错误日志位于 /var/log/httpd/error_log
[Sun Apr 22 03:31:03 2012] [notice] Digest: generating secret for digest authentication ...
[Sun Apr 22 03:31:03 2012] [notice] Digest: done
[Sun Apr 22 03:31:04 2012] [notice] Apache/2.2.15 (Unix) DAV/2 PHP/5.3.3 configured -- resuming normal operations
[Sun Apr 22 07:57:56 2012] [error] [client 218.199.92.61] File does not exist: /var/www/html/phpMyAdmin
[Sun Apr 22 15:51:09 2012] [error] [client 218.199.92.61] File does not exist: /var/www/html/admin
[Sun Apr 22 19:00:15 2012] [error] [client 135.109.198.196] File does not exist: /var/www/html/manager
[Sun Apr 22 21:16:46 2012] [error] [client 69.53.223.250] File does not exist: /var/www/html/manager
[Sun Apr 22 21:26:22 2012] [error] [client 186.28.229.2] File does not exist: /var/www/html/manager
[Sun Apr 22 22:00:51 2012] [error] [client 175.41.136.19] File does not exist: /var/www/html/manager
[Sun Apr 22 23:15:10 2012] [error] [client 218.199.92.61] File does not exist: /var/www/html/admin
[Mon Apr 23 06:53:08 2012] [error] [client 218.199.92.61] File does not exist: /var/www/html/admin
[Mon Apr 23 11:20:57 2012] [notice] caught SIGTERM, shutting down
[Mon Apr 23 12:26:48 2012] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Mon Apr 23 12:26:48 2012] [notice] Digest: generating secret for digest authentication ...
[Mon Apr 23 12:26:48 2012] [notice] Digest: done
[Mon Apr 23 12:26:49 2012] [notice] Apache/2.2.15 (Unix) DAV/2 PHP/5.3.3 configured -- resuming normal operations
[Mon Apr 23 13:31:20 2012] [error] [client 41.161.9.163] File does not exist: /var/www/html/favicon.ico
[Mon Apr 23 13:31:20 2012] [error] [client 41.161.9.163] File does not exist: /var/www/html/favicon.ico
[Mon Apr 23 14:54:06 2012] [error] [client 218.199.92.61] File does not exist: /var/www/html/db
[Mon Apr 23 15:56:24 2012] [error] [client 41.161.9.163] Directory index forbidden by Options directive: /var/www/html/
[Mon Apr 23 19:36:45 2012] [notice] caught SIGTERM, shutting down
[Mon Apr 23 19:38:24 2012] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Mon Apr 23 19:38:24 2012] [notice] Digest: generating secret for digest authentication ...
[Mon Apr 23 19:38:24 2012] [notice] Digest: done
[Mon Apr 23 19:38:25 2012] [notice] Apache/2.2.15 (Unix) DAV/2 PHP/5.3.3 configured -- resuming normal operations
[Mon Apr 23 19:40:32 2012] [notice] caught SIGTERM, shutting down
[Mon Apr 23 19:40:33 2012] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Mon Apr 23 19:40:33 2012] [notice] Digest: generating secret for digest authentication ...
[Mon Apr 23 19:40:33 2012] [notice] Digest: done
[Mon Apr 23 19:40:33 2012] [notice] Apache/2.2.15 (Unix) DAV/2 PHP/5.3.3 configured -- resuming normal operations
[Mon Apr 23 19:40:40 2012] [notice] caught SIGTERM, shutting down
[Mon Apr 23 19:40:40 2012] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Mon Apr 23 19:40:40 2012] [notice] Digest: generating secret for digest authentication ...
[Mon Apr 23 19:40:40 2012] [notice] Digest: done
[Mon Apr 23 19:40:40 2012] [notice] Apache/2.2.15 (Unix) DAV/2 PHP/5.3.3 configured -- resuming normal operations
[Mon Apr 23 19:40:57 2012] [notice] caught SIGTERM, shutting down
[Mon Apr 23 19:40:58 2012] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Mon Apr 23 19:40:58 2012] [notice] Digest: generating secret for digest authentication ...
[Mon Apr 23 19:40:58 2012] [notice] Digest: done
[Mon Apr 23 19:40:58 2012] [notice] Apache/2.2.15 (Unix) DAV/2 PHP/5.3.3 configured -- resuming normal operations
[Mon Apr 23 19:41:29 2012] [notice] caught SIGTERM, shutting down
[Mon Apr 23 19:43:58 2012] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Mon Apr 23 19:43:58 2012] [notice] Digest: generating secret for digest authentication ...
[Mon Apr 23 19:43:58 2012] [notice] Digest: done
[Mon Apr 23 19:44:00 2012] [notice] Apache/2.2.15 (Unix) DAV/2 PHP/5.3.3 configured -- resuming normal operations
[Mon Apr 23 19:57:28 2012] [notice] caught SIGTERM, shutting down
[Mon Apr 23 19:57:29 2012] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Mon Apr 23 19:57:29 2012] [notice] Digest: generating secret for digest authentication ...
[Mon Apr 23 19:57:29 2012] [notice] Digest: done
[Mon Apr 23 19:57:29 2012] [notice] Apache/2.2.15 (Unix) DAV/2 PHP/5.3.3 configured -- resuming normal operations
[Mon Apr 23 22:40:29 2012] [error] [client 218.199.92.61] File does not exist: /var/www/html/dbadmin
[Mon Apr 23 23:03:09 2012] [error] [client 200.98.148.21] File does not exist: /var/www/html/manager
[Tue Apr 24 05:49:22 2012] [error] [client 220.226.188.32] File does not exist: /var/www/html/user
[Tue Apr 24 06:37:11 2012] [error] [client 218.199.92.61] File does not exist: /var/www/html/myadmin