Thursday, August 27, 2009

SharePoint SP2 Alternate Access Mapping issue... Fixed

The fix for the Alternate Access mapping issue has been published in August 2009 CU : http://support.microsoft.com/kb/973410.

The Kb states the following, amongst the issues fixed :

'You have a Web application that has more than five incoming URLs. You cannot change Alternate Access Mappings (AAM) settings after you install the 2007 Microsoft Office system cumulative update that was released in April 2008.'

<Update >
Please be aware of the new issue found in these updates. Read here.
</Update >

Saturday, August 8, 2009

SharePoint Alternate Access Mappings explained....my way!

I see many people confused about AAMs, their role and their usage. Therefore, I decided to write a post about them and explain in clear English what are they, when to use them and where to define them.

What AAms are?

AAMs are different urls mapped to the same application in order to give access to the same content using different zones. We cannot talk about AAMs without talking about web application zones. Each SharePoint web application can have five zones : Default, Internet, Intranet, Extranet and Custom. Each zone can have its own authentication provider. For example, Integrated windows authentication for the Default zone, Anonymous access for the Internet zone and Form based authentication for the Extranet zone. All the five zones share the same Database. i.e. the same content, but each one has its proper IIS web Site. Each zone has a public url. When we create a web application, the default zone is created. Let's say "http://default.mycompany:80". Then, we can extend this web application to the four remaining zones if we need to. For our example, we will extend our web application to the Internet zone "http://www.mycompany.com" and the Extranet zone "http://extranet.mycompany.com".

When to use AAMs?

Suppose that for convenience, I want my internal users to access the default zone using a more simplified url. What to do? Create a new AAM (http://mycompany) and map it the default zone. Now, the default zone can be accessed using whether http://mycompany or http://default.mycompany:80.

Suppose again that my company has been sold to a rich man. The urls I created for my web application are no longer valid. What to do to rename my web application urls from mycompany to hiscompany? Backup the content, create a new web application with new urls then restore the content? Yes, it could be. However, there is a better and simpler solution : AAMs. Create new AAMs, i.e.
"http://default.hiscompany:80", "http://mycompany", "http://www.hiscompany.com" and "http://extranet.hiscompany.com" and map each url to the appropriate zone.

Where do I define these AAMs?

I'm glad you asked! Go to Central Admin > Operations > Alternate Access Mappings, under the Global Configuration section.

It goes without saying that the urls we are talking about must be first defined in the DNS and IIS.

I hope I have shed more light on AAMs by now. Nevertheless, if you have any question, feel free to ask.

Hope this post is helpful.