This parameter lets binding the proxy connection to a non-local address.
Upstream will see the connection as coming from that address.
When used with $remote_addr, upstream will accept the connection from real
client address.
Example:
proxy_bind $remote_addr transparent;
The main proxy function ngx_stream_proxy_process() can terminate the stream
session. The code, following it, should check its return code to make sure the
session still exists. This happens in client and upstream initialization
functions. Swapping ngx_stream_proxy_process() call with the code, that
follows it, leaves the same problem vice versa.
In future ngx_stream_proxy_process() will call ngx_stream_proxy_next_upstream()
making it too complicated to know if stream session still exists after this
call.
Now ngx_stream_proxy_process() is called from posted event handlers in both
places with no code following it. The posted event is automatically removed
once session is terminated.
Resolved warnings about declarations that hide previous local declarations.
Warnings about WSASocketA() being deprecated resolved by explicit use of
WSASocketW() instead of WSASocket(). When compiling without IPv6 support,
WinSock deprecated warnings are disabled to allow use of gethostbyname().
Once upstream is connected, the upstream buffer is allocated. Previously, the
proxy module used the buffer allocation status to check if upstream is
connected. Now it's enough to check the flag.
When configured, an individual listen socket on a given address is
created for each worker process. This allows to reduce in-kernel lock
contention on configurations with high accept rates, resulting in better
performance. As of now it works on Linux and DragonFly BSD.
Note that on Linux incoming connection requests are currently tied up
to a specific listen socket, and if some sockets are closed, connection
requests will be reset, see https://lwn.net/Articles/542629/. With
nginx, this may happen if the number of worker processes is reduced.
There is no such problem on DragonFly BSD.
Based on previous work by Sepherosa Ziehau and Yingqi Lu.
There is no need to set "i" to 0, as it's expected to be 0 assuming
the bindings are properly sorted, and we already rely on this when
explicitly set hport->naddrs to 1. Remaining conditional code is
replaced with identical "hport->naddrs = i + 1".
Identical modifications are done in the mail and stream modules,
in the ngx_mail_optimize_servers() and ngx_stream_optimize_servers()
functions, respectively.
No functional changes.
When client or upstream connection is closed, level-triggered read event
remained active until the end of the session leading to cpu hog. Now the flag
NGX_CLOSE_EVENT is used to unschedule the event.
