IonixIP/Smarts IP: Can I limit snmp-server view blocks supplied in Ionix IP/Smarts IP?; What is the loss of functionality based upon supplied SNMP view blocks?; Very large ARP tables observed and the CPU is spiking on rediscovery

Products

• VMware Smart Assurance

Issue/Introduction

Symptoms:


Can I limit snmp-server view blocks supplied in Ionix IP/Smarts IP?
Loss of functionality based upon supplied SNMP view blocks in Ionix IP/Smarts IP


Very large ARP tables observed and the CPU is spiking on rediscovery in Ionix IP/Smarts IP

Environment

VMware Smart Assurance - SMARTS

Cause

The devices which are locking up have very large ARP tables and the CPU is spiking on rediscovery.

Resolution

Limiting the availability of SNMP views to keep the above problem from occurring can impair the Ionix IP/Smarts IP functionality for root cause determination and basic monitoring.

For example, consider the following view blocks which could be configured on the device:

snmp-server view BLOCK ipAddrEntry.*.10.177.255.47 included
snmp-server view BLOCK ipAddrEntry.*.10.150 included
snmp-server view BLOCK ipAddrTable excluded
snmp-server view BLOCK ip.22 excluded

This configuration could cause the following problems:

• ipAddrTable is excluded from the BLOCK view and ipAddrEntry is included. This can cause an issue with the Auto-Discovery feature, which depends on ipAddrTable.
   
• ip.22 (ipNetToMediaTable) is excluded from the BLOCK view. During discovery, this table is essential to map IP and MAC addresses. Without this table, relationships in the topology may get affected. See <IP_BASE_DIR>/smarts/rules/discovery/ic-arp-cache.asl file, and see the logs for OID 1.3.6.1.2.1.4.22.