Magento products not showing up consistently in frontend

I have Magento site running with 20000 plus products. Sometimes it does not show the products in the frontend. It says "There are no products matching the selection", but the products are still there in the backend site.

I know I have to run re-indexing process, and whenever I complete the re-indexing process all products are there in the frontend.

So now, my question is: Why this is happening again and again? This is now fourth time I faced this probl开发者_如何学编程em. I want to know the real causes of this issue. I am very afraid.

Thanks

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The two most likely cuplrits are caching and indexing problems (unless of course you are using a clustered database, in which case that is probably the culprit). If it's feasible on your site (or on a dev environment, which I am sure you had the foresight to create), disable Magento's caching temporarily and see if that alleviates the issue. Also try disabling the flat_catalog settings to see if that is having an effect.

Also make sure that your browser cache is set to always refresh from the server.

Hope that helps!

Thanks, Joe

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It sounds like you need to setup your cronjobs to re-run the indexes. Certainly with prices, the custom price indexes are only valid for a set period of time, then the cronjob extends those periods if the Catalog Price Rule is still active.

Here is a wiki post on the process of setting up your cronjobs.

Note that cron itself can cause problems, so as Joseph suggests, make sure you have a dev and staging environment setup that mirrors production so that you can check the configuration.