Installation guide

Using the Qpid Management Framework (QMF) provided by the libvirt-qpid package. This
utilizes QMF to track guest migrations without requiring a full host cluster to be present.
Shared storage can be provided by either iSCSI or KVM shared block devices backed by either
host block storage or by file backed storage (raw images).
Red Hat Enterprise Virtualization Management (RHEV-M) versions 2.2+ and 3.0 currently support
RHEL 5.6+ and RHEL 6.1+ clustered guests.
Guest clusters must be homogeneous (either all RHEL 5.6+ guests or all RHEL 6.1+ guests).
Mixing bare metal cluster nodes with cluster nodes that are virtualized is permitted.
Fencing is provided by fence_scsi in RHEV-M 2.2+ and by both fence_scsi and fence_rhevm in
RHEV-M 3.0. Fencing is supported using fence_scsi as described below:
Use of fence_scsi with iSCSI storage is limited to iSCSI servers that support SCSI 3
Persistent Reservations with the preempt-and-abort command. Not all iSCSI servers
support this functionality. Check with your storage vendor to ensure that your server is
compliant with SCSI 3 Persistent Reservation support. Note that the iSCSI server shipped
with Red Hat Enterprise Linux does not presently support SCSI 3 Persistent Reservations,
so it is not suitable for use with fence_scsi.
VMware vSphere 4.1, VMware vCenter 4.1, VMware ESX and ESXi 4.1 supports running guest
clusters where the guest operating systems are RHEL 5.7+ or RHEL 6.2+. Version 5.0 of VMware
vSphere, vCenter, ESX and ESXi are also supported; however due to an incomplete WDSL
schema provided in the initial release of Vmware vSphere 5.0, the fence_vmware_soap utility does
not work on the default install. Refer to the Red Hat Knowledgebase
https://access.redhat.com/knowledge/ for updated procedures to fix this issue.
Guest clusters must be homogeneous (either all RHEL 5.7+ guests or all RHEL 6.1+ guests).
Mixing bare metal cluster nodes with cluster nodes that are virtualized is permitted.
The fence_vmware_soap agent requires the 3rd party VMware perl APIs. This software
package must be downloaded from VMware's web site and installed onto the RHEL clustered
guests.
Alternatively, fence_scsi can be used to provide fencing as described below.
Shared storage can be provided by either iSCSI or VMware raw shared block devices.
Usage of VMware ESX guest clusters is supported using either fence_vmware_so_ap or
fence_scsi.
Usage of Hyper-V guest clusters is unsupported at this time.
7.2.1. Using fence_scsi and iSCSI Shared St orage
In all of the above virtualization environments, fence_scsi and iSCSI storage can be used in place
of native shared storage and the native fence devices.
fence_scsi can be used to provide I/O fencing for shared storage provided over iSCSI if the iSCSI
target properly supports SCSI 3 persistent reservations and the preempt and abort command.
Check with your storage vendor to determine if your iSCSI solution supports the above
functionality.
⁠Chapt er 7 . Virt ualizat ion and High Availabilit y
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