It is important that the UTC times of all managers and scalability servers, which are involved in a move operation, are synchronized in order for record age comparison to work. Consideration has been taken to different time zones.
It is assumed that software on the computer being moved is left intact during the move. If any software is manually removed or added during the move, it is imperative that any changes are also recorded at the new domain manager, which now manages the computer, for example, by manually deleting install records for software, which was manually removed.
Every time an software delivery (SD) agent connects to a manager or scalability server, a message is passed to the agent. The message contains information about the address of the domain manager managing the agent and the current scalability server's UTC time. The agent stores the domain manager address locally. When the agent detects a change in the domain manager address between two consecutive connections, the previous domain manager address is remembered for each of the targets handled by the SD agent (for example the user profiles)
The previous domain manager address is passed up the SD infrastructure to the new domain manager, which attempts to perform the move operation.
This activity is repeated for each of the targets handled by the agent and every time the agent moves to a new domain manager.
The agent is using the passed scalability server UTC time in calculating its reference counter, which is a sort of timestamp of every connection. The reference counter is passed up the infrastructure to the domain manager. It is used to determine which of two compared target records are more recent during a move operation.
Since the SD manager time cannot always be trusted, the SD agent performs a sanity check by comparing it with its previous reference counter. If the current scalability server UTC time indicates that the previous reference counter should be increased, the UTC time is used to calculate the new reference counter.
However, if the current manager UTC time indicates that the reference counter should be decreased, the SD agent discards this UTC time, and just increments the previous reference counter to ensure that a greater value is used for each connection to the scalability server.
For newly installed SD agents, the reference counter is always initialized using the current scalability server UTC time.
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