Domain Controller Settings
The domain controller lookup setting is used to verify connectivity to a domain controller, and that the cached domain controller is still active. Domain controller lookups are expensive operations, often taking from 6 to 10 seconds to complete. XA provides login times that are typically less than a second because the domain controller lookup does not happen on every request. However, because the controller name is cached, and not verified on every request, the possibility of a down server due to power outage, or a reboot may occur. XA must therefore confirm on a periodic basis that the domain controller is still functional. This provides a failover mechanism to backup domain controllers in the event that the cached controller is no longer available. Recommended settings are between 5 and 10 minutes, as domain controllers are typically available. Longer times will affect login performance in the event of a down server, as a new domain controller selection would be delayed by the value specified here.
The "domain controller check failover count" is a value indicating the number of failures to contact the domain controller before a failover event will be triggered. If the domain controller is busy processing other user requests, it could timeout when the XA server attempts to verify connectivity. While the domain controller may still be operational, it may be slightly unresponsive. Therefore, this setting indicates the number of retries to perform before assuming the server is down. Recommended values are between 5 and 10. While larger values are supported, it may have a performance impact if the failover is delayed due to an overburdened server and a high retry count.
The "domain controller check failover count" corresponds to this registry key:
HKEY_LOCAL_MACHINE\SOFTWARE\HealthCast\ExactAccess\XADSNT
PDCCheckBeforeFailCount: reg_dword