We recommend the Domino server and migration workers be on the same network segment as the Exchange server (1 Hop).
There are other factors that cause slow migrations that are not related to our product. This has to do with the migration workstation, anti-virus software, Domino & Exchange servers, workstation QoS, etc.
Test network through put.
Check Notes setup and connections (Trace Connection test)
Test where the bottleneck is within each segment.
Check the response time between Outlook and Exchange (Cloud).
Find the bottleneck by performing the following tests:
1. Migrate from a local Notes database to local .PST file - If the migration is slow, then there is an issue with Migrator for Notes or the migration workstation. Check health of the machine (CPU, RAM, Disk i/o, etc)
2. Migrate from Local Notes NSF to Exchange - - If slow, then there is a problem with the connection to Exchange/Exchange Online tenant
3. Migrate from Domino to local .PST - If slow, then there is a problem with the connection between the Domino server and the migration workers
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