DX NetOps Spectrum 22.2.5+ SNMPv3 Performance Improvements

Products

• DX NetOps
• CA Spectrum

Issue/Introduction

DX NetOps Spectrum 22.2.5+ SNMPv3 Performance Improvements

Environment

Release: 22.2.5+

Resolution

Three updates have been introduced to the 22.2.5 release that will help with SNMPv3 Performance Issues. They are listed below.

Added a new VNM model Attribute, FlushSnmpv3ProfilesInterval (0x13429)

- If the value of this attribute is non-zero, DX NetOps Spectrum starts the timer to flush the SNMP v3 remote profiles periodically. This non-zero value represents the interval in days.
- If the attribute value is set to 0, timer will be stopped. By default, the value is 0
- The above feature is targeted to flush the remote profile cache (reset snmpv3 authentication) for every device at a certain interval and let the cache rebuild for every v3 device based on its poll.

Added a new .vnmrc parameter v3_profile_hash_factor that allows you to configure Hash Factor for remote profiles

- All the remote SNMPv3 profiles are maintained in a hashTree(cache) and the value of 256 is the load factor used to build the hash key. This feature is useful for customers who are not using unique profiles / same profile across multiple devices. Setting a prime high value gives a more unique hash key for better performance.

Added a new .vnmrc parameter tds_local_v3_profiles_store=true 

- Optimizes the performance of the local SNMPv3 profiles search by storing them in a hash table instead of a list.

Additional Information

What is meant by “remote profiles”?

- Whenever a user creates a SNMPv3 profile through the OneClick Discovery Console, that is called Local Profile (doesn't have a SNMPv3 EngineID). During a discovery then subsequently a poll, Spectrum tries with all the local profiles or its associated community string and forms the remote cache (includes the SNMPv3 EngineID) based on the response received from the device.  Remote profile is an internal cache maintained by SS to decrypt the SNMPv3 response. This cache gets recreated for every SS restart.