5.2.6 Considerations for using a hot-standby configuration in a virtualization environment (when using KVM)
If virtualization is achieved by using Kernel-based Virtual Machine (KVM) technology, hot-standby switchover can be performed in units of guest OSs in which HA Monitor runs. For details about how to specify the settings for running a virtual machine by using KVM, see the RHEL documentation.
This subsection covers the points to consider when performing hot-standby switchover in units of guest OSs.
- Organization of this subsection
(1) Considering the guest OS to be created in a hot-standby switchover configuration
The difference of HA Monitor operation between a KVM-based virtualization environment and a normal environment is only whether HA Monitor monitors the guest OS or processor on the host. In a KVM-based virtualization environment, SCSI reservation is used for the shared disk. In this case, hot-standby switchover can be achieved only between KVM guest OSs.
To secure reliability, create a hot-standby switchover configuration by using guest OSs that run on different processors.
(2) Checking the version of HA Monitor
In a KVM-based virtualization environment, make sure that the versions of all HA Monitor products in the hot-standby switchover configuration are 01-76 or later.
If you use the same monitoring paths as in the existing system, set the monitoring paths in such a manner that the HA Monitor in the existing system cannot connect to a host in the hot-standby configuration.
(3) Checking the machine environment
To use KVM for virtualization, make sure that the machine environment meets the following conditions:
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The environment requires a shared disk and uses SCSI reservation.
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Fibre Channel connection is used for the shared disk.
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If the shared disk is connected by multipath routing, the Device Mapper Multipath Tool (DMMP) on the guest OS side must control the multipath routing. Note that a logical path controlled by DMMP on the host OS side cannot be assigned to the guest OS.