I am evaluating nginx pop3 proxy function and encounter 1 problem. Here is my setup:

OS: RedHat FC7 2.6.21-1.3194.fc7 #1 SMP Wed May 23 22:35:01 EDT 2007 i686 i686 i386 GNU/Linux GCC: gcc version 4.1.2 20070502 (Red Hat 4.1.2-12) Nginx version: 0.5.26 Config option: --with-debug --with-mail --with-select_module

Nginx config: daemon on; user root; worker_processes 10;

error_log logs/error.log debug; pid logs/nginx.pid;

#maximum total connections of each worker events { worker_connections 100; # use select; debug_connection 127.0.0.1; }

mail { auth_http localhost:8088/auth.php;

pop3_capabilities "TOP" "USER"; pop3_auth plain; imap_capabilities "IMAP4rev1" "UIDPLUS";

#pop3 configuration server { listen 110; protocol pop3; proxy on; } }

Test case: - A mailbox with message around 10M large - Use telnet to port 110, issue the USER/PASS command to login - Issue RETR 1 to download the 10M message - Close the connection by pressing Ctrl-] then 'q' right after RETR command is issued

At this time, Netstat shows that the connection from nginx to the backend POP3 server remains connected.

Now, I repeat the above test case with "use select" turns on in nginx.conf. This time, I don't see the connection to backend pop3 remains after my client connection to nginx is terminated in the middle. I suspect this is something to do with epoll call?

I only did the test on POP3 proxy, not sure if it has the same behaviour on HTTP.

Please let me know if you need more information.