Understanding SharePoint - Part 6 - Duplicate Content Sources bound to multiple indexes causes duplicate alerts to be fired

I had a theory that this caused problems and validated it today while working with a customer who has a large number of content sources spread across multiple indexes.

Note: First of all, poking around through the UI to look at all the details of indexes, content sources, etc is a real pain. Thus (You guessed it :)) I wrote a tool to gather and export this information so that I could look at it holistically. It was actually a modification to the SPSAddCS tool in the SharePoint utility suite, just modified to use XML and added a "Read" operation to it to dump the data in XML.

Once I've had a chance to test it out in more detail, I'll post the code for it as well.

Since this customer had 4+ portal indexes with approximately 10 content sources per index, it made it allot easier to look at everything and spot the problem quickly.

Once I saw that they had two content sources pointing to the exact same content yet on two different indexes, it was a simple matter of setting this up on a plain Jane standalone SharePoint Portal Server 2003 box to validate.

I validated this using the following setup on my local test server.

Created a plain IIS web site and placed a default web page with the following contents:

<html>

<body>

<P>Hello!</P>

<P>Keith Richie was here</p>

</body>

</html>

Issued a search in the portal for “Keith Richie”, then selected “Alert Me” to create a portal alert, with its’ settings set to immediate

Added a content source to this plain web site did a full crawl and confirmed that the notification was sent

Created a new index

  • Created a duplicate content source to the same plain web site bound to this index
  • Made an update to the default web page
  • Did a full crawl on both indexes, and I received two notifications about the same change

Created a third new index

  • Created a third duplicate content source to the same plain web site bound to this index.
  • Made an update to the default web page
  • Did a full crawl on all three indexes, and I received three notifications about the same change

Depending on your structure, and Exclude/Include rules created, this can occur for SharePoint sites as well

You ARE however, blocked from creating a duplicate content source on the same index, but not on a completely different index.  When you attempt to create a duplicate source address on the same index, you'll get the following error message:

“The object you are trying to create already exists. Try again using a different name. “

But if you are creating this on a different index, you will not get a warning.

In MOSS 2007, you are not allowed to even have multiple indexes unless you create multiple SSPs.  I'm not 100% up to snuff on the WSS 3.0/MOSS 2007 alert architecture, but I am very curious and would suspect that you would encounter the same problem, and could confuse users.

 - Keith


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