Lots of "No route to host" in Nginx error log

[xufengnju]

Hi All,

We got lots of "No route to host" in Nginx error log.
'
2010/01/05 22:28:01 [error] 29366#0: *26063920 connect() failed (113: No route to host) while connecting to upstream, client: 60.217.152.205, server: test.com, request: GET /herundong/index.php HTTP/1.1, upstream: http://x.y.z.a:80/herundong/index.php, host: events.test.com  ' 
Using curl on the Nginx proxy server like 
curl -v -H "Host: events.test.com" http://x.y.z.a/herundong/index.php 
works as expected.
I searched in Nginx source code, and find even no 'No route to host' in its source code.

Nginx version: 0.7.63
Backend are Apache servers.

Current Nginx connections ~2k;
Current Apache Connections ~800(counting all active and inactive connections)
I saw on some connections of apache, there was a high Send-Q on established nginx-apache connections.
Current Apache load average is under 1;

Any suggestions?

Thanks in advance.

2010-01-06 



xufengnju 
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