Best practices

Object filtering for load balancing

If VMware vCenter Server inventory is larger than the recommended scalability guidelines for one BMC PATROL Agent, you can balance the load across multiple BMC PATROL Agents by leveraging the BMC PATROL for VMware vSphere object-filtering capability. This section describes various options for object filtering by using regular expression.

How to use regular expression

We can use regular expressions to filter objects. For example, to filter a certain host, use the following pconfig rule:

"/VSM/VC/vCenterServerName/FilterHosts" = {REPLACE = "DB.*|OS.*\A1"}

In the previously mentioned example, "DB.*|OS.*\A1" string has the following three components:

Datacenter filtering (recommended)

We can balance the load by monitoring some datacenters with one BMC PATROL Agent and the remaining with other agents. Datacenter filtering ensures that you do not have any duplicate monitoring of entities across multiple BMC PATROL Agents.

For example

A VMware vCenter Server has 110 ESXi hosts and 5000 virtual machines. With multiple datacenters, ESXi hosts and virtual machines are distributed as follows:

Using datacenter filtering, the load can be distributed across two BMC PATROL Agents as shown in the following table:

The load can be distributed by performing the following steps:

1. Include monitoring of DC1 on the first BMC PATROL Agent by using the following pconfig rule:
   "/VSM/VC/vCenterServerName/FilterDatacenters" = {REPLACE = "DC1\A1"}
2. Exclude the monitoring of DC1 from the second BMC PATROL Agent by using the following pconfig rule,
   "/VSM/VC/vCenterServerName/FilterDatacenters" = {REPLACE = "DC1\A2"}

Cluster filtering

If VMware vCenter Server has only one datacenter or if one datacenter is very large compared to the others when combined, you can achieve load balancing by monitoring some clusters by using one BMC PATROL Agent and the remaining clusters by using other agents. The disadvantage of this filtering is duplicate monitoring of some datastores, which are shared across hosts within a datacenter.

For example

Consider a VMware vCenter Server having 100 ESXi hosts and 5000 virtual machines in a single datacenter. ESXi and VMs are distributed across 4 clusters as explained in the following table:

Using cluster filtering, the load can be balanced across two BMC PATROL Agents as shown in the following table:

Load balancing can be achieved by performing the following steps:

1. Include monitoring of Prod_Cluster01 and Prod_Cluster03 clusters on the first BMC PATROL Agent by using the following pconfig rule:
   "/VSM/VC/vCenterServerName/FilterClusters" = {REPLACE = "Prod_Cluster01|Prod_Cluster03\A1"},
2. Exclude the monitoring of Prod_Cluster01 and Prod_Cluster03 clusters from the second BMC PATROL Agent by using the following pconfig rule,
   

   "/VSM/VC/vCenterServerName/FilterClusters" = {REPLACE =

   "Prod_Cluster01|Prod_Cluster03\A2"},

Host filtering

If VMware vCenter Server does not have clusters or if there is only one cluster, you can achieve load balancing by monitoring some ESXi hosts using one BMC PATROL Agent and the remaining hosts by using other agents.

Host filtering can result in duplicate monitoring of some clusters (if hosts are part of clusters) and datastores, which are shared across the hosts within a datacenter.

 For example

Consider a VMware vCenter Server environment having 100 ESXi hosts and 5000 virtual machines. Using host filtering, the load can be balanced across two BMC PATROL Agents. This can be achieved by performing the following steps:

1. Use the regular expression which matches 100 ESXi servers and monitor them by using the first BMC PATROL Agent with the following pconfig rule:
   "/VSM/VC/vCenterServerName/FilterHosts" = {REPLACE = "DB.*|OS.*\A1"}
2. Use the same regular expression with exclude option to monitor the remaining ESXi servers by using the second BMC PATROL Agent with the following pconfig rule:
   "/VSM/VC/vCenterServerName/FilterHosts" = {REPLACE = "DB.*|OS.*\A2"}

Combined filtering

You can also use a combination of the previously mentioned filtering based on your VMware vCenter Server inventory.