I have 7 sites,in every site i have only one domain controller. Do i need to create bridgehead server in every site?

All Domain controllers are Global Catalog , and all have DNS role install

Hello, there is no need to create bridgeheads manually. Just make sure that your AD sites are well configured, your DCs are linked to correct sites and that your subnets are created correctly and linked to correct sites. That is all! This posting is provided "AS IS" with no warranties or guarantees , and confers no rights. Microsoft Student Partner 2010 / 2011 Microsoft Certified Professional Microsoft Certified Systems Administrator: Security Microsoft Certified Systems Engineer: Security Microsoft Certified Technology Specialist: Windows Server 2008 Active Directory, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Network Infrastructure, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Applications Infrastructure, Configuration Microsoft Certified Technology Specialist: Windows 7, Configuring Microsoft Certified IT Professional: Enterprise Administrator Microsoft Certified IT Professional: Server Administrator

By default, the Active Directory replication topology generator, the Knowledge Consistency Checker (KCC), automatically chooses servers to act as bridgehead servers. However, if you are an administrator, you may select one or more domain controllers in the site to be preferred bridgehead servers. These servers are used exclusively to replicate changes collected from the site. Even though you may have administratively configured several domain controllers as preferred bridgehead servers, the KCC chooses one of these servers to become the bridgehead server for the site. http://support.microsoft.com/kb/271997http://www.virmansec.com/blogs/skhairuddin