Setting global limits on the use of RHV resources
You can use the NetBackup Resource Limit dialog from the NetBackup administration console to control the number of simultaneous backups that can be performed on an RHV resource type. The settings apply to all NetBackup policies for the currently selected master server.
For example, to avoid overloading the overall RHV cluster, you can place a limit on the number of concurrent backup jobs per RHV Cluster. To control input output overhead on the storage domain array, you can limit the number of concurrent backups per storage domain.
Three Resource Limits available for RHV:
Backup Jobs per DataCenter
Backup Jobs per Cluster
Backup Jobs per StorageDomain
To set limits on the use of RHV resources
- In the NetBackup Administration Console, click Host Properties > Master Servers and double-click the NetBackup master server.
- In the Properties screen, scroll down in the left pane and click Resource Limit.
- Under Application, click RHV.
- Click in the Resource Limit column to set the maximum NetBackup usage for a particular resource type. The settings apply to all policies.
For each resource type, the default is 0, (No Limit).
Following example illustrates how these limits control simultaneous backups. The settings must be done according to RHV configuration in your environment.
When NetBackup connects to the RHV environment for backup, it makes 1 connection per disk present on the VM. So, if a VM has 2 disks then NetBackup would make 2 connections with the RHV node.
So, consider a case where RHV manager is managing 2 clusters with 2 nodes in each cluster. Let's consider every node is hosting 20 VMs with 2 disks on each VM.
When the job runs, there would be 80 concurrent jobs start if no Resource Limit is set which is default behavior. RHV recommends up to 10 disk connections concurrently per node in the cluster. In the example of each VM with two disks, 5 VMs per node can be ideally backed up concurrently. Hence, in this case of a cluster with two nodes, it is recommended to backup upto 10 VMs concurrently. When the Backup Jobs per Cluster is set to 10, this limit is enforced.
Since one data center can manage multiple clusters, Backup Jobs per DataCenter resource limit could be higher than Backup Jobs per Cluster. You need to determine the values by evaluating the effect of backup on overall environment.
Storage domain in RHV can server multiple clusters in a data center. It serves to protection VM as well as backup. Its performance is dependent on type of storage technology - FC, iSCSI, NFS, gluster etc. Hence limit on storage domain using Backup Jobs per StorageDomain can be set based on characteristics of storage domain technology and limit can be higher than Backup Jobs per Cluster.