Secondary VM Needed: VMware Fault Tolerance

VMware Fault Tolerance enables continuous availability for a virtual machine in the event of a VMware host failure.

A Secondary VM Needed alarm is triggered when a problem exists with the secondary VM where the primary VM is in a fault tolerant group. The primary fault tolerant group may consist of mission critical Oracle VMware and/or SQL Server on VMware applications. Address this problem quickly to avoid errors or downtime for those applications.

To trigger the Secondary VM Needed alarm, one of the following conditions must exist:

  • For primary VMs, the virtual machine has at least one registered secondary VM, but it/they are not enabled.
  • For secondary VMs, this state indicates that the secondary is disabled.
  • For primary VMS, this state indicates that it is powered on and has at least one enabled secondary, but no secondary is currently active.

Definition

VMware Fault Tolerance is a feature that provides guest redundancy for most mission-critical applications that cannot tolerate any interruption of service or data loss, including applications running Oracle VMware, SQL Server on VMware, and other database environments. It can be enabled on any virtual machine that resides in an HA cluster.

When VMware Fault Tolerance is enabled on a primary VM, a secondary VM is created on a different host in the cluster. The secondary VM runs in virtual lockstep with the primary VM. The following events are triggered when a failure occurs:

  • A transparent failover takes place in which the secondary VM continues execution from the exact point where the primary left off.
  • The secondary VM becomes the new primary VM.
  • A new secondary virtual machine is started on another host.

During this failover, there is no data loss or noticeable service interruption.

Note: Fault Tolerance can only be enabled on VMs that meet specified fault tolerance requirements.

Confio IgniteVM

Confio IgniteVM helps identify the impact of secondary VM needed alerts for sites running Oracle on VMware, SQL Server on VMware, and other virtual databases. IgniteVM helps DBAs maintain performance and availability on virtual servers. IgniteVM is the only virtualization-aware database monitoring solution.

Learn more about IgniteVM solutions for: