To Extend or Not to Extend - That is the Question

At one point or another in every SharePoint administrator's career there comes the point where they have to take an Intranet SharePoint deployment and allow Extranet or Internet access to it for other stakeholders of the organization. This is a simple enough process, the only trick is whether to use the built-in functionality to extend a web application or to simply add some alternate access mappings.



If you choose to use the Extend Web Application feature in SharePoint, which is located in Central Administration under Application Management -> SharePoint Web Application Management. Choose the Extend an existing Web application option. It will then ask you to choose a Web application to extend and then the same settings that are available when you create a Web application - the name of the IIS site, port, hostheader, path, authentication provider, allow anonymous, and whether to use SSL. Under the load balanced URL section there is a new item that says zone. This correlates to the IE zones and also to the alternate access mapping that SharePoint will create. The options are default, Intranet, Internet, Custom, and Extranet. When you click the ok button SharePoint will create the IIS site and will create the alternate access mapping automatically.



The second option is to go into the alternate access mappings yourself and add them. AAM is located in Central Administration ->Operations -> Global Configuration -> Alternate Access Mappings. You would simply select the Alternate Access Mapping Collection from the drop down and then click on the Edit Public URLs link. You then have the option of adding the URLs for each of the 5 zones. Then just click save and the alternate access mappings are added.



Either way will allow alternate access to your SharePoint site. The choice is yours.