Drupal Multisite installation, old stories showing up

Question

I have a multisite Drupal installation with about 20 urls pointing to the same code base and a common database. I have around 20,000 visitors visiting all sites daily which I hope would increase.

I am using 2 servers currently- one being the webserver Apache 2 on Linux Platform and the other is the database server- MYSQL.

Sometimes, my sites start showing old content that date backs to months. Any idea why such a behavior and how it can be reverted?

Clearing the cache solves the problem only temporarily but the problem reappears.

Thanks in advance to a kind helper :)

Answer 1

There can be many things that can cause this bug, however, you state that clearing the cache "solves" it.

Drupal has this concept called content access. That mechanism is also found in domain module, organic groups, i18n and other, less famous modules.

These modules all have one important sideeffect: you can no longer use caching in Drupal! Some modules, like domain, attempt to get caching back, by taking matters in their own hands, and cache themselves. But the bottomline is:

Do not switch on cache when you have a content-access module enabled.

You should have gotten a warning on the cache (admin » settings » performance) page, about this fact. Does it show you such a warning? If so, switching off cache, is the only correct route. But will have a side-effect: performance will drop.

If that is not the case, you will have to give us more information: errors from error-logs, watchdog-details, logged queries on times that it goes wrong etceteras.