Qemu Guest Agent has many features like shutdown/restart VM guest and also provides information about the VM guest. You can see basic information which is provided by qemu-guest-agent in Adminportal ( Compute –> Virtual Machines –> Click the VM –> Guest Info ). This post will list the essential features that Qemu Guest Agent provides. […]
RHV
RHV – Understanding of Qemu Guest Agent
Libvirt uses the Qemu guest agent running inside a VM. This post will elaborate on how the Qemu agent act as a communication channel between KVM host and the guest. Communication Protocol The communication protocol used to fetch information of the VM OS or issue commands to the Guest OS is Qemu Machine Protocol(QMP). QMP […]
Understanding RHV Cluster Migration Policy
In RHV 4.3.6, there are three migration policies: Minimal downtime, Suspend workload if needed and Post-copy migration. This post will explain them in details. Live VM migration mainly involves the transfer of VM’s CPU, memory, and I/O state from the source KVM host to the destination KVM host. With regards to “Minimal downtime” and “Suspend […]
Understanding Cluster Fencing Policy in RedHat Virtualization (RHV)
This post will illustrate the fencing policy for a cluster. Enable fencing By default, fencing is enabled on the cluster. However, it can be disabled if it is required. If this option is disabled, that means it will complete disabling fencing for hosts in the cluster. This is usable in the situation when there are […]
List of All Available Configuration Options in vdsm.conf for VDSM
This post provides a comprehensive list of all configuration options available in vdsm.conf for vdsm. The file vdsm.conf.sample includes a commented list of all available options in vdsm.conf. This is provided by vdsm package. You can find it at: /usr/share/doc/vdsm-4.30.33/vdsm.conf.sample For example, check the configurable VDSM tunables for volumes: $ less /usr/share/doc/vdsm-4.30.33/vdsm.conf.sample |grep -i -C2 […]
RedHat Virtualization (RHV) – Engine Config Options
This document will provide all engine config options, type, valid values, and descriptions. Key Type Valid Values Description AffinityRulesEnforcementManagerEnabled Boolean – Enable/Disable Affinity Rules Enforcement Manager AffinityRulesEnforcementManagerRegularInterval Integer – Affinity Rules Enforcement Manager interval in minutes. AsyncTaskPollingRate Integer – Async Task Polling Rate (in seconds) AsyncTaskZombieTaskLifeInMinutes Integer – Zombie tasks life-time in minutes AuditLogAgingThreshold Integer […]
Understanding Power Management in RedHat Virtualization (RHV)
This post will deep dive into RHV Power Management. What is Host Power Management(Fence)? When Power Management is configured, RHV can reboot the hosts that are in NonOperational or NonResponsive state. RHV supports the following power management devices: American Power Conversion (apc) IBM Bladecenter (Bladecenter) Cisco Unified Computing System (cisco_ucs) Dell Remote Access Card 5 […]
Understanding Live Merge in RedHat Virtualization (RHV)
Live Merge is Snapshot Deletion while the VM is up and running. A live merge is initiated when a user clicks the ‘delete’ command associated with a disk snapshot while VM is running. Live merge is an asynchronous operation and the process is quite complex. Here is the table of live merge flow of events: […]
Understanding Volume Chains in RedHat Virtualization (RHV)
It’s important to understand the volume chains for troubleshooting snapshot create/delete issues. This post will explain the correlation of volume chains. Volume chains in both Engine Database and Host need to be checked as you need to check if the REAL status of the disks is the same as what you see in the database. […]
Red Hat Virtualization (RHV) Log Files
This document lists the main log files on ovirt-engine and kvm host of RHV 4.3.x. oVirt engine logs Log File Log Rotation /var/log/ovirt-engine/engine.log Reflects all RHV GUI crashes, Active Directory lookups, Database issues, and other events. /var/log/ovirt-engine/host-deploy/* Log files from hosts deployed from the RHV. /var/lib/ovirt-engine/setup/* Tracks the installation and upgrade of packages associated with […]