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azureazure-virtual-machineazure-devtest-labs

Throttling/errors when attaching data disks to VM in Azure?


I am trying to performance test each of the different size tiers (A, D, DS, F...etc) of virtual machines in Azure devtest labs. In doing so, I need to attach the maximum number of data disks that each size will accept, however I keep getting two errors when trying to attach the disks.

  • Failed to add data disk to virtual machine, the request is being throttled.
  • Number of write requests for subscription '(subscription number)' exceeded the limit of '1200' for time interval '01:00:00'. Please try again after 'X' minutes. (time has been as low a 3 minutes and high as 30 minutes)

Currently I will attach a disk, wait 10 minutes, then try to attach another disk with about a 50% success rate.

Is there any way to avoid these errors, like a setting change to the subscription, or am I just trying to attach the disks too quickly?


Solution

  • Is there any way to avoid these errors, like a setting change to the subscription, or am I just trying to attach the disks too quickly?

    In brief, there is no way to avoid this error.

    There are several limits and restrictions on Azure. And your issue is caused by one of them.

    The default limit of Resource Manager API Writes is 1200 per hour.

    Normally, if you want to raise the limit above the Default Limit, you can open an online customer support request at no charge. But the limits cannot be raised above the Maximum Limit value.

    Unfortunately, the Maximum Limit of Resource Manager API Writes is same with the default limit, which is 1200 per hour. So, to my knowledge, there is no way to raise this limit.

    For detailed information about the limits on Azure, please refer to the link below:

    Azure subscription and service limits, quotas, and constraints