Auto-Balanced Collector Groups

Resource assignment in LogicMonitor has traditionally followed a one-to-many structure, where a single Collector monitors multiple resources, but each resource can only be assigned to one Collector. While practical, this model can complicate resource management, load distribution, and scalability.

Auto-Balanced Collector Groups (ABCGs) address the above challenges by assigning resources to multiple Collectors within a group. ABCGs provide the following benefits:

• Dynamic load balancing—Automatically reassigns resources from overloaded Collectors to others within the group, preventing oversubscription
• Improved failover handling—Redistribution of resources among the remaining Collectors when a Collector in an ABCG goes down
• Simplified capacity management—Streamline the process of adding resources and managing load across multiple Collectors

ABCG monitoring thresholds are based on raw instance counts and not current load or weighted instances. Every 30 minutes, LogicMonitor reviews the instance counts per Collector in the group.

If a Collector exceeds its monitoring threshold, the following rebalancing actions take place:

• LogicMonitor rebalances the load by moving resources with the highest instance counts from the overloaded Collector to the Collector with the lowest load in the ABCG.
• If moving a resource would cause the recipient Collector to exceed its threshold, the next largest resource is considered.
• This process continues until the overloaded Collector is within its threshold or all resources have been evaluated.

In an ABCG group, two or multiple collectors can have the same IP address. However, their Preferred collector must not be the same and must not be set to Auto Balanced. Let us understand this using the following scenarios:

Scenario	Collector A	Collector B	Conclusion
Collectors with similar IP address	IP address—127.0.0.1 Preferred collector—Auto Balanced	IP address—127.0.0.1 Preferred collector—Collector B	Collector A and B cannot be part of the same ABCG because they have similar IP address.
Collector with similar IP address and Preferred collector	IP address—127.0.0.1 Preferred collector—Collector B	IP address—127.0.0.1 Preferred collector—Collector B	Collector A and B cannot be part of the same ABCG because they have similar IP address and Preferred collector.
Collector with unique Preferred collectors and are not set to Auto Balanced	IP address—127.0.0.1 Preferred collector—Collector A	IP address—127.0.0.1 Preferred collector—Collector B	Collector A and B can be part of the same ABCG because they have unique Preferred collectors and none of them is set to Auto Balanced.

Instance Threshold Limits for Auto-Balanced Collector Group

The instance count threshold of a Collector in an ABCG is automatically calculated based on the configured threshold value of the ABCG and the available RAM on the Collector. By default, the threshold is set to 10,000 instances, reflecting the capacity of a medium-size Collector with 2 GB RAM. You can adjust the threshold value in the configuration for ABCG using the following table as a reference.

The number of instances a Collector can handle is determined using the following formula:

Number of instances = (Target_Collector_mem/Medium_mem)^1/2 * Medium_Threshold

For example, if a user sets a threshold for a medium-size (2 GB) Collector to 10,000, for a large-size (4 GB) Collector, the threshold will be scaled to:

14140 instances = (4/2)^1/2*10000 

Collector Requirements for Inclusion in Auto-Balanced Collector Groups

All Collectors in an ABCG must meet the following requirements:

• Monitor themselves. For more information, see Monitoring your Collectors.
• Same network access to resources monitored by the ABCG.
• Same operating system to ensure the continuity of metrics and similar monitoring capabilities.
• Same collector version.

Setting Up an Auto-Balanced Collector Group 

1. In LogicMonitor, navigate to Settings > Collector> select an existing collector group for enabling auto-balancing.

2. Select   Manage at the top-right corner.
   
3. Toggle on the Auto Balanced Collector Group switch to enable auto-balancing for the selected collector group.
   

4. Select Save.

Assigning Resources to Auto-Balanced Collector Group

1. In LogicMonitor, navigate to Resource Tree> Resources> and select an existing resource.
2. Select   Manage at the top-right corner.
3. In the Collector Group field, select an auto-balanced collector group.
   The Preferred Collector field automatically updates to Auto Balanced.
   

4. Select Save.
   The auto-balancing is enabled for the resource.