How does rate limits work when an ARM API call hits multiple regions

Question

The Azure documentation on ARM API requests mentions that API requests get throttled based on the region where the resource is hosted on.
So how does calls like listing VMs. (Azure CLI command is **az vm list **) get throttled? If VMs are hosted in multiple regions, does this single call hit the counter for rate limits in all the regions where we need to fetch the VM resources?

Answer 1

Hello @Venkata Gudivada ,

Thank you for reaching out to Microsoft QnA. Happy to answer your question.
No, this single list call will not hit the individual regions where your resources (VMs in your case) are hosted. Rather, this call will go to the ARM, and ARM itself will fetch the list of the VMs from the metadata of all resources that it stores. This call will only go to the ARM instance in one specific region, i.e, the nearest region to your current location from where you are making the call.

To help understand better, think of ARM as a consistent management layer that stores the metadata for all resources. So, whenever anyone makes a get/list request, the list of resources will be fetched from the ARM itself, and it will not go to the individual regions where the resources are located.

Hope this helps.

--------------------

Please don't forget to Accept as Answer and Upvote and if you think my response was helpful.