NSX-T Manager UI does not work intermittently, and Search API is intermittently failing with a CircuitBreaker exception having text as "Data too large".

Products

• VMware NSX

Issue/Introduction

• When there are too many concurrent queries at the same time, the search APIs fail intermittently if the OpenSearch/Elasticsearch query cache is occupying a large portion of allocated heap.
• NSX-T Manager UI does not work intermittently, or certain data is not getting populated on UI.
• For example, when accessing Networking->Network overview page from NSX UI, none of the component's information was loaded.
• Error message seen on NSX UI:
  "Failed to get the report - An unknown error has occurred".
• Validate search-manager.log under /var/log/search.
  2024-03-26T06:57:35.900Z WARN http-nio-127.0.0.1-7440-exec-284 IndexingMetadataHelper 4492 - [nsx@6876 comp="nsx-manager" level="WARNING" reqId="<UUID-redacted>" subcomp="manager" username="[e-mail]"] Could not fetch indexing position from ES, error: ElasticsearchStatusException[Elasticsearch exception [type=circuit_breaking_exception, reason=[parent] Data too large, data for [<http_request>] would be [1862171586/1.7gb], which is larger than the limit of [1860491673/1.7gb], real usage: [1862169944/1.7gb], new bytes reserved: [1642/1.6kb]]

Environment

VMware NSX

Cause

Due to frequent searches on any entity having number of entities greater than 10k the queries are getting cached. As a result, the heap taken by OpenSearch is significantly increasing.

Resolution

This issue is resolved in VMware NSX 4.2.0

Workaround:
Clear the Query cache of ElasticSearch/OpenSearch using command:
curl -X POST "localhost:9200/_cache/clear?query=true"