The re-deploy functionality of Azure VM is to transfer VM's to a new host and is for ARM based deployments and not the ASM.
However, I am sharing information that can help you plan your Classic VM migration to ARM. Document to refer for more information on this.
From the documentation, Migration workflow is as follows:
Key Migrations Points:
o Validate
o Prepare
o Commit / Abort
It is recommend to replicate your environment and perform a test migration, document reference.
There are four supported scopes of migration, check this document.
o Migration of virtual machines (NOT in a virtual network)
o Migration of virtual machines (in a virtual network)
o Migration of storage accounts
o Migration of unattached resources
Migration of virtual machines (in a virtual network) - Preferred - Please not that your applications running on top of VMs (classic) do not incur downtime during the migration. For most VM configurations, only the metadata is migrating between the Classic and Resource Manager deployment models. The underlying VMs are running on the same hardware, in the same network, and with the same storage. The management-plane operations may not be allowed for a certain period of time during the migration. However, the data plane continues to work.
As per this document, Cloud Services containing web and worker roles cannot migrate to Azure Resource Manager. The web/worker roles must first be removed from the virtual network before migration can start.
For information on the Unsupported features and configurations, refer to this document.
For Classic to ARM migration FAQs, please check this page.
Hope this information is helpful.
Incase you need more help on migration, requesting you to open a support case. Support team can help in the migration.
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