The news cache is an extension of the news server. When the news cache does not have the requested news in its cache, it connects to the Reader server component of the news server through NNTP. The Reader server obtains the data that the news cache requests from the news storage device, in this case, a NetApp® filer.
Note
The Feeder server and Reader server components of the news server might be on separate servers, as shown in the previous illustration, or they might be on the same server.
NetCache provides controls that enable you to set the rate at which the news cache checks the news server for new articles and canceled articles.
The news cache continues to service news requests, even if the news server is unavailable. If the client requests news data that is in the cache and has not yet expired, NetCache returns that data to the client. If the client requests news data that is not in the cache, NetCache returns the message "400 service discontinued, server disconnected" to the client. The connection between the client and the cache is then closed.
If the news server is unavailable while NetCache is checking for new or canceled articles, the client receives the "400 service discontinued, server disconnected" message, and the connection between the news cache and the client is closed.
News caching resumes as usual when the news server is available again.
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Part No. 210-00372
File: nntpdpl3.htm
Last updated: 11/13/02 18:11:44