Assume that you have an environment that contains users' roaming profile location (server-based profiles). The server-based profiles are accessed from Windows 7 Service Pack 1 (SP1) or Windows Server 2008 R2 SP1 through a domain-based Distributed File System (DFS) share. It takes longer than expected to load or unload the profiles. Additionally, you may notice the following behavior:
- When you view the network traces of the slow transactions, you notice that the DFS API request NetrDfsGetInfo or dfs_GetInfo is taking some time.
Note The combined load of all domain controllers in a big domain against the Primary Domain Controller (PDC) might become so big that the connection to the PDC fails and that the DFS API does not respond with a valid path. When this happens, the roaming profile cannot be loaded after the delay. Please review the "More Information" section in this article. - When you view the processing of the request at the DFS server, which is usually the local domain controller (local DC), you see that it has communication with the PDC. There are two basic scenarios where a delay happens:
- When the DFS volume has many links and the PDC is attached over a low wide area network (WAN) link, it can take a long time to retrieve the data that the local DC requests by using the LDAP protocol.
- When the local DC cannot reach the PDC, it spends significant time retrying a connection with it.