Firewall devices dropping SNMP packets that are larger than 512 bytes from CA Spectrum

Products

• CA Spectrum
• DX NetOps

Issue/Introduction

Firewall devices are generating messages saying that CA Spectrum is sending SNMP packets that exceed the buffer size of 512. This is
   causing Spectrum to assert Management Agent Lost alarms on the associated models.

Environment

Release: 21.2, 22.2
Component: Spectrum Core / SpectroSERVER

Cause

The snmp buffer on the firewall devices cannot process snmp packets larger than 512 bytes and therefore does not repond.

Resolution

Set the Message_Size/0x1197b attribute on the device model and all associated interface and application models to 512 or less (Default value 1500). This must be done
   on all associated interface and application models because these models will also poll the associated device for specific functionality. 

The Locator can be used to find all interface and application models based on device model name. When found, select all returned models and launch the Attribute Editor
   to change the value of the Message_Size attribute id 0x1197b en masse.