What is the difference between High Availability On-Premise Pollers and On-Premise Poller Groups?

What is the difference between High Availability On-Premise Pollers and On-Premise Poller Groups?

High Availability On-Premise Pollers and On-Premise Poller Groups are two different approaches to ensuring service continuity and reliability in a monitoring setup. Let's examine the differences and explore how to maintain service continuity using them.

A comparison between High Availability On-Premise Pollers and On-Premise Poller Groups

The table below highlights the differences between High Availability and On-Premise Poller Groups:
Feature​
High Availability On-Premise Pollers
On-Premise Poller Groups
Mapping
One-to-one (primary and standby)
Many-to-many (group-based): one or more On-Premise Pollers assigned to more than one monitor based on standby
Failover
The Standby On-Premise Poller takes over
Any available On-Premise Poller in the standby list takes over
Load balancing
No
Yes
Scalability
Limited (per On-Premise Poller pair)
High (multiple On-Premise Pollers per group)

Achieving High Availability with On-Premise Poller Groups

You can achieve High Availability using On-Premise Poller Groups, but the mechanism is different from classic one-to-one High Availability.

In an On-Premise Poller Group, High Availability is accomplished through redundancy and load balancing. Multiple On-Premise Pollers are available to take over if any On-Premise Poller fails, providing both fault tolerance and continuous monitoring.
Unlike the strict primary-standby relationship in classic High Availability, On-Premise Poller Groups allow any On-Premise Poller in the group to assume the monitoring role, making the setup more flexible and scalable.

If any On-Premise Poller goes down, one from the standby pool automatically takes charge of the monitoring tasks. Any affected monitors associated with the On-Premise Poller that went down seamlessly resume polling through the new Standby On-Premise Poller. Once the unavailable On-Premise Poller becomes available again, it will become part of the standby group.

  1. The High Availability feature for On-Premise Pollers
  2. On-Premise Poller Groups