In order for a tree merge to be successful, all servers will need to have a copy of the tree key(s) from all the original trees.
Before merging, you should identify the key servers for each of the tree keys (W0 and W1) in all the trees.
After merging, for each of the tree keys (W0 and W1) you should add the names of all the SD key servers to the corresponding object from all the merged trees. For each object (W0 and W1), the final list must contain the names of the SD key servers, for that object, from all the trees being merged.
NOTE:If either of the trees have been created in AES 256-bit tree key, then all servers in both trees MUST be upgraded to eDirectory 9.0 before merging.