Hi @Nilesh Patel ,
>What are all the comparability level 150,140,140,120,110 ( not able to understand these levels)
>I am doing assessment of one server can I do the assessment of other servers(3-4 servers) in parallel in DMA tool?
Yes, you can create multi project for the assessment of other migration as below screenshot. They run in parallel in the DMA tool.
For other questions, I suggest you running DMA for this migration, this tool can perform assessments to identify feature parity and database compatibility issues when moving your SQL Server to Azure SQL managed instance. Such as discovering the compatibility issues, or discovering breaking changes and behavior changes that will effect migration etc. It will present you with a report identifying all those, as well as possible fixes for the different Database Compatibility level available for your chosen target. Refer to MS document Overview of Data Migration Assistant.
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