Each server in the cluster has a a search index that is synced from one of the servers every 15 minutes. This was done because appending to an index can't happen on a nfs because of flock; see [documentation](http://framework.zend.com/manual/en/zend.search.lucene.index-creation.html#zend.search.lucene.index-creation.creating) (or else the index would be on a shared folder that all servers access). 

The issue that I'm running into is that if an action is taken that requires modifying of the index, the modifications happens on the local copy of the index and I need a way to sync those changes back to the parent in the least intrusive way as possible (so that the changes propagate to all servers in the cluster by the next sync). 

I tried referencing the parent server index via http but this won't work because mkdir can't be done over http. Is there a way to reference the index of a remote server? If there is an entirely different approach available that will be considered as well