System Administration Guide: Resource Management and Network Services

NCA to Httpd Request Flow

The following list shows the request flow between the client and the web server.

An HTTP request is made from the client to the web server.
If the page is in cache, the in-kernel cache web page is returned.
If the page is not in cache, the request goes to the web server to retrieve or update the page.
Depending on the HTTP protocol semantics that are used in the HTTP response, the page is cached or not and then it is returned to the client. If the Pragma: No-cache header is included in the HTTP request, the page is not cached.

Interpositioning Library for Door Server Daemon Support

Many web servers use AF_INET sockets. By default, NCA uses AF_NCA sockets. To correct this situation, an interpositioning library is provided. The new library is loaded in front of the standard socket library, libsocket.so. The library call bind() is interposed by the new library, ncad_addr.so. If the status is enabled in /etc/nca/ncakmod.conf, the version of Apache that is included with the Solaris 9 release is already set up to call this library. If you are using IWS or Netscape servers, see "How to Load the NCA Socket Utility Library" to use the new library.


2. Managing Web Cache Servers Caching Web Pages (Reference) NCA Architecture


	NCA to Httpd Request Flow The following list shows the request flow between the client and the web server. An HTTP request is made from the client to the web server. If the page is in cache, the in-kernel cache web page is returned. If the page is not in cache, the request goes to the web server to retrieve or update the page. Depending on the HTTP protocol semantics that are used in the HTTP response, the page is cached or not and then it is returned to the client. If the Pragma: No-cache header is included in the HTTP request, the page is not cached. Interpositioning Library for Door Server Daemon Support Many web servers use AF_INET sockets. By default, NCA uses AF_NCA sockets. To correct this situation, an interpositioning library is provided. The new library is loaded in front of the standard socket library, `libsocket.so`. The library call `bind()` is interposed by the new library, ncad_addr.so. If the status is enabled in `/etc/nca/ncakmod.conf`, the version of Apache that is included with the Solaris 9 release is already set up to call this library. If you are using IWS or Netscape servers, see "How to Load the NCA Socket Utility Library" to use the new library.