Registry based VDA Registration
List more than one controller on ListOfDDCs registry key separated by a space to prevent registration issues if a controller is not available.
• Example DDC5.xd.local DDC6.xd.local
o HKEY_LOCAL_MACHINE SoftwareCitrixVirtualDesktopAgentListOfDDCs
o 64Bit – HKEY_LOCAL_MACHINESoftware Wow6432CitrixVirtualDesktopAgentListOfDDCs (REG_SZ)
Ensure all values listed under ListOfDDCs map to a valid fully qualified domain name to prevent startup registration delays.
XenDesktop 5.5 and higher supports registration groups by adding parenthesis around each group. This feature addition allows you to create groups of brokers to load balance Virtual Desktop Agent registrations. Once you have defined groups of brokers, registrations attempts are made against Broker 1 in Group 1, then against Broker 2 in Group 1, and so on. If all registration attempts against Group 1 brokers fail, attempts are made against Group 2 brokers, and so on.
• Example (DDC1.local.domain DDC2.local.domain) (DDC3.local.domain DDC4.local.domain)
Note:The VDA (Citrix Desktop Service) will randomly select DDCs from the list (grouped or ungrouped) until a successful connection to a DDC is established.
CTX130369 – Citrix XenDesktop 5.5 – Issues Fixed in This Release
CTX118976 – How to Configure XenDesktop to Function Without an Organizational Unit in Active Directory
CTX132536 – Worker Unregisters at Session Launch
You can read the entire knowledgebase article here.