Skip to main content
Question

compute-changed-regions API returns 401 UNAUTHORIZED after ~15 minutes for specific VMs

  • June 16, 2026
  • 4 replies
  • 15 views
S

We are using the Data Protection v4.1 API compute-changed-regions endpoint from Prism Central 7.5 (AOS 11.0.0.1) to retrieve changed regions for VM recovery points.

For most VMs, the workflow completes successfully. However, for VMs with large changed data disks, the API consistently fails with:

401 UNAUTHORIZED

The failure occurs approximately 15 minutes after the operation starts.

Our current steps are:

  1. compute-changed-regions is invoked successfully for cluster prism element API - api/dataprotection/v4.1/content/recovery-points/{recoveryPointExtId}/vm-recovery-points/{vmRecoveryPointExtId}/disk-recovery-points/{extId}/$actions/compute-changed-regions
  2. Nutanix begins computing changed regions.
  3. The VM disks are highly fragmented and may contain a very large number of changed extents.
  4. Results are returned through pagination.
  5. The client continues fetching paginated results.
  6. Total processing time exceeds approximately 15 minutes.
  7. A subsequent page retrieval request returns 401 UNAUTHORIZED.

Additional observations:

  • The same VMs same disks fail consistently.
  • Other VMs disks succeed.
  • Recovery points and disk recovery points still exist when the failure occurs.
  • The initial compute-changed-regions request succeeds; the failure occurs later in the workflow.

Questions:

  1. Is it expected for pagination or continuation tokens associated with compute-changed-regions to expire after approximately 15 minutes?
  2. Is there a documented timeout for Data Protection v4.1 API pagination sessions or JWT/session tokens used by this workflow?
  3. Can a large number of changed extents or highly fragmented disks cause compute-changed-regions processing to exceed the token/session lifetime?
  4. Is there a supported method to increase the timeout for Data Protection API sessions, JWT tokens, pagination tokens, or continuation tokens?
  5. Are there any known issues in Prism Central 7.5 / AOS 11.0.0.1 related to compute-changed-regions returning 401 for long-running operations?

Any guidance on expected behavior, timeout configuration, or recommended troubleshooting would be appreciated.

4 replies

jarrodl
Forum|alt.badge.img+2
  • jarrodl
  • Vanguard
  • June 18, 2026

I’m not to familiar with DR yet. Did you have to configure an account between your primary and secondary sites, If so. Is that account an AD user, Local User or Service account?

Platform Engineer | Nutanix Technology Champion 2026
T
Forum|alt.badge.img+1

Here, the architecture is as following. DR solution runs inside a Virtual Machine sitting in same Nutanix Cluster. The module of DR solution invokes Prism Central / Element APIs to query Changed Areas for a snapshot. This API is described in above post.

The core issue is that the session used in API for querying changed regions times out after 15 mins, even though there are API requests made within that time. E.g. For a disk with large change area, the API is invoked in a loop till the time all the changed areas are returned. Even when the APIs are invoked one after the other, the session times out & API returns 401 Unauthorized error after 15 mins. 

This is 100% reproducible error for disks with large change data.

jarrodl
Forum|alt.badge.img+2
  • jarrodl
  • Vanguard
  • June 18, 2026

Here, the architecture is as following. DR solution runs inside a Virtual Machine sitting in same Nutanix Cluster. The module of DR solution invokes Prism Central / Element APIs to query Changed Areas for a snapshot. This API is described in above post.

The core issue is that the session used in API for querying changed regions times out after 15 mins, even though there are API requests made within that time. E.g. For a disk with large change area, the API is invoked in a loop till the time all the changed areas are returned. Even when the APIs are invoked one after the other, the session times out & API returns 401 Unauthorized error after 15 mins. 

This is 100% reproducible error for disks with large change data.

I am trying to understand how this authenticate with the Nutanix API endpoints. Because we have a similar issue with our API due to the volume and frequency of request we are sending where it causes that 401 error.

We have this issue due to using an AD Account, If it’s not using an AD account, then this might be a different to the issue we have with our API 

Platform Engineer | Nutanix Technology Champion 2026
jarrodl
Forum|alt.badge.img+2
  • jarrodl
  • Vanguard
  • June 18, 2026

The other thing I was able to find in the documentation was a object limit.

If you run the checks from this article, does the object size exceed 4000?

https://portal.nutanix.com/page/documents/kbs/details?targetId=kA0VO000000CspR0AS

Platform Engineer | Nutanix Technology Champion 2026
Terms & ConditionsAccessibility statement