Inside Activate
Activate and Active Directory
How Activate Finds Domain Controllers
4 min
this article describes how activate finds domain controllers (dc's) within active directory activate attempts to find a close dc to a particular computer during a number of operations, like creating a mailbox, resetting a password and adding a user to a folder activate utilizes the standard windows mechanism with some extensions for non windows machines the underlying windows mechanism is described here http //support microsoft com/kb/247811 this uses dns entries to find the appropriate information based on active directory sites and sub sites description activate tries the following process to find a dc for the a specified computer 1\ it uses the underlying dsgetdcname in windows to connect to the specified computer and request a domain controller in the specified domain 2\ if the remote machine is not a windows machine for returns and error the following process is used to attempt to find a valid domain controller in the specified domain 1\ look up the ip address of the machine in active directory (dns must be working) 2\ resolve the ip address to a valid site in active directory using dsaddresstositenames on the local domain controller 3\ look up a domain controller in the returned site using dsgetdcname 3\ if the above fails then a dc cannot be found general troubleshooting if activate fails to find a dc it logs and error in the following format "unable to find dc for \[computername] from \[domain]/\[site]" this means that windows could not find a dc for the specified computer in the domain near the site specified and generally means that active directory is not configured correctly likely errors 1\ check that the ip address for the \[targetcomputer] is specified as a valid site in active directory sites 2\ check network and dns settings on the \[targetcomputer] 3\ check ad replication (does the dc near the target machine have the correct dns information) 4\ check or remove dead domain controllers 5\ check trustees and name resolution for remote domains basic troubleshooting process from the activate server open a command line 1\ check the \[targetcomputer] is correct ping \[targetcomputer] check that you can resolve and connect to the specified computer resolve any access denied or name resolution issues 2\ check if a dc can be found nltest /server \[targetcomputer] /dsgetdc \[domain] this will probably fail is activate is failing dcdiag can be used to further diagnose root caused 3\ check site settings for computer nltest /server \[targetcomputer] /dsgetsite 4\ run dcdiag and fix issues dcdiag /v a detailed trouble shooting guide for the underlying windows process is located in this article http //support microsoft com/kb/247811