fyi, I got confirmed that it is sufficient to change the EngineID in the Nodes table
Currently we do this directly via scheduled SQL job, maybe we'll trigger this by script in future through the API....
change the bottom 50% of the Nodes table:
UPDATE X SET EngineID =
(SELECT EngineID FROM Engines WHERE ServerName = '[POLLER SERVER X]')
FROM
(SELECT TOP 50 PERCENT * FROM Nodes ORDER BY NodeID DESC)
X
change the top 50% of the Nodes table:
UPDATE Y SET EngineID =
(SELECT EngineID FROM Engines WHERE ServerName = '[POLLER SERVER Y]')
FROM
(SELECT TOP 50 PERCENT * FROM Nodes ORDER BY NodeID ASC)
Y
