As the operating systems you are referring are mostly not supported, It is highly recommend that you consider a strategy forward on supported OS.
I have reached out to internal team on your ask and below are the answers I got:
- Is it possible to enable azure monitor for Legacy OS systems (Windows 2003,Windows 2000, Windows NT, RHEL 7.0 and Below) hosted in azure stack HCI?
Azure Monitor uses an agent. The requirements for this agent are here. Suffice to say, Windows NT/2000/2003 are not supported. - Is it possible to enable azure Backup for Legacy OS systems (Windows 2003,Windows 2000, Windows NT, RHEL 7.0 and Below) hosted in azure stack HCI?
Windows NT, 2000 and 2003 are unsupported. - What are recommended ratios for physical vs. virtual CPU cores in Azure Stack HCI? (1:2,1:4)
Azure Stack HCI has no recommended ratios for physical to virtual cores. It depends on the workloads. For example, lightly loaded web servers could easily have ratios of over 12:1 while a
scale up SQL Server could have a ratio of 2:1. This is workload dependent. - Monitoring is configured but data is not being collected
I don’t understand the question, but the docs for Azure Monitor are here. - Is it possible to backup VMs running on HCI stack to Azure (Azure Backup Center)
Yes, Azure Backup can be used to back up VMs to Azure, Doc ref.
Hope this helps.
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