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Concurrent Modification

URI: https://docs.ankatech.co/errors/concurrent-modification
HTTP Status: 409 Conflict

When you see this

The resource you tried to update was changed by another request between the time you read it and the time you wrote it. Your write was rejected to prevent silently overwriting the newer state.

Common Causes

  • Two clients updating the same key, policy, or tenant at the same time.
  • A stale version of the resource being submitted after another change landed.
  • Retrying a write without first re-reading the current resource state.

Response Example

{
  "type": "https://docs.ankatech.co/errors/concurrent-modification",
  "title": "Concurrent Modification",
  "status": 409,
  "detail": "The resource was modified by another request. Re-read the current state and retry.",
  "instance": "/api/v3/admin/tenants/00000000-0000-0000-0000-000000000001/policies",
  "correlationId": "550e8400-e29b-41d4-a716-446655440000",
  "timestamp": 1730000000
}

Content-Type: application/problem+json — the response follows RFC 7807 Problem Details.

How to Resolve

  1. Re-fetch the resource to obtain its current state.
  2. Re-apply your change on top of the latest version.
  3. Re-submit the request. If conflicts persist, serialize concurrent writers or add a short backoff between attempts.

For full schema definitions, examples, and interactive testing, see the Developer Hub Reference.