Cisco ACI GUI slow performance due to VNA API health queries

Products

• Spectrum
• Virtual Network Assurance

Issue/Introduction

Cisco ACI fabric experiences severe GUI slowness and high NGINX CPU usage caused by frequent VNA API requests requesting unsupported health data․ ​‌​​​‌‍​‌

 

ERROR MESSAGE:

"Health MO not supported on IFC for this MO"

 

SYMPTOMS:

• Severe slowness in the Cisco ACI GUI interface․

• High CPU utilization for NGINX process on APIC controllers․

• Stopping VNA service (systemctl stop wildfly) immediately resolves the slowness․

• Excessive NGINX log entries for resolveHealths errors․

 

CONTEXT: The issue occurs when VNA version 24․3․10 polls large-scale ACI environments, specifically targeting /api/node/class/fvAEPg․json with health-count parameters․

 

IMPACT: Large-scale environments with high IP route counts (e․g․, 32,000+) experience controller overload․

 

 

Environment

DX NetOps VNA: 24.3.10

Cause

VNA 24․3․10 uses a small default pagination size (300) for IP routes, resulting in excessive API calls (e․g․, 110+ calls for 32,000 routes) ․ Furthermore, queries include health data requests for objects where health monitoring is not supported by the APIC․

RELATED RESOURCES:

• Fixed Issues Documentation: https://techdocs․broadcom․com/us/en/ca-enterprise-software/it-operations-management/dx-netops/25-4/Performance-Monitoring-with-DX-Performance-Management/release-notes/fixed-issues․html

• Defect ID: DE177024

Resolution

PREREQUISITES:

• Access to VNA Swagger UI․

• Root/Administrative access to the VNA server filesystem․

• Identify the specific UUID for the ACI collector instance ․

   

STEPS:

1․ IDENTIFY SCALE AND UPGRADE PATH: Review VNA statistics via Swagger UI (GET /v1/inventory/stats) ․ Upgrading to version 25․4․2 or later is the recommended fix ․ Newer versions use pagination (page size 1000) which reduces API calls by approximately 66%․

2․ WORKAROUND - DISABLE IP ROUTES POLLING: If an upgrade is not feasible, disable IP route collection to reduce load․

A․ Stop the ACI Engine via Swagger: Navigate to: Admin -> PUT /v1/admin/engines/{engineid}/{action} ․

B․ Modify configuration file: Edit: /opt/CA/VNA/collector/ACI_[UUID]/repository/deviceConfig/ACI-Inventory․xml ․ Locate section: <Acquisition desc="ACI IP Routes"> ․ Change <Poll>Yes</Poll> to <Poll>No</Poll> (typically at line 844)․

C․ Start the ACI Engine via Swagger: Navigate to: Admin -> PUT /v1/admin/engines/{engineid}/{action} ․

VERIFY SUCCESS:

• Search gateway logs (/opt/CA/VNA/wildfly/standalone/log/gateway․log) for the pattern ACI_[UUID]:ipRoutes․

• After disabling, the search should return no new matches․

• Verify that APIC NGINX CPU usage returns to normal levels․