Hello WANG Yuzhi,
Thanks for your question.
Using data disks to store applications and data offers the following benefits over using the OS disk:
- Improved Backup and Disaster Recovery
- More flexibility and scalability
- Performance isolation
- Easier maintenance
- Improved security and access control
The above is documented here: https://learn.microsoft.com/en-us/azure/virtual-machines/managed-disks-overview
Please let me know if you have further questions.
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