Hello @Pavel yannara Mirochnitchenko ,
Thank you for reaching out to the Microsoft Q&A platform.
Based on the details you provided, here are my recommendations:
Azure Spot Instances: Azure Spot Instances can be a cost-effective option for running non-critical workloads. Spot Instances allow you to take advantage of unused Azure capacity at a significantly reduced cost compared to regular instances. However, keep in mind that Spot Instances can be interrupted with little notice if Azure needs the capacity back. So, it's important to have a plan in place to handle interruptions, such as using availability sets or scaling sets to ensure high availability.
Secondary HDD Disk: Yes, you can detach and reattach a disk from one server to another. This can be a good option if you want to recreate the server or move the disk to a different server. However, keep in mind that detaching a disk from a running server can cause data loss or corruption, so it's important to shut down the server before detaching the disk.
Small Local Disk with Bigger HDD Disk: This can be a good option for cost savings, as long as the application can run on a smaller local disk. You can attach a larger HDD disk to the server to store the application files. However, keep in mind that the larger disk will be billed separately from the server, so make sure to factor in the cost of the disk when calculating the overall cost.
Overall, it's important to balance cost savings with performance and reliability. Make sure to choose the right instance size and disk configuration to meet the needs of your application, and consider using availability sets or scaling sets to ensure high availability and handle interruptions.
Hope this helps.
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