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Microsoft Hyper-V will not boot virtual SCSI devices
“Each IDE controller can have two devices. You can not boot from a SCSI controller. This means an IDE disk will be required. The boot disk will be IDE controller 0 Device 0. If you want a CDROM it will consume an IDE device slot.” Source:MSDN Blog
The hypervisor that runs the virtual BIOS does not support booting from a SCSI controller, today, but it does support the following boot devices: CD IDE Legacy Network Adapter Floppy
The root reason is SCSI in a synthetic device and there is no VMBUS until after boot.
One might think that this shouldn’t be a problem, after all, the virtual machines can still boot from regular IDE-based virtual disks. So where’s the catch?
The main problem is related to the fact that in Virtual Server, virtual SCSI controllers have major performance benefits over virtual IDE controllers. In Virtual Server, it is recommended to attach the Virtual Disks to one or more SCSI controllers to improve disk input/output (I/O) performance. IDE is limited to one transaction at a time, regardless of whether the bus is physical or virtual. This means that a virtual machine with two virtual hard disks attached to the IDE adapter is limited to a single transaction for both disks. By contrast, a SCSI controllers allows for multiple simultaneous transactions, which provides better performance than disks attached to the IDE controllers.
This performance bottleneck of virtual IDE and technical limitations of virtual SCSI will oblige customers to have two virtual disks for each VM. A configuration hard to setup in P2V migration scenarios, and hard to manage on large scale deployments.
Note that since Hyper-V is still in Beta phase, all numbers are subject to change as are the behaviors. So there might be hope, after all…
Note: Under Virtual Server 2005, contrary to common sense, the performance of emulated SCSI controllers is slower than that of emulated IDE controllers. The reason for this is that the SCSI controller is a lot more complicated to emulate than the IDE controller. However, this changes once you have Virtual Machine Additions installed, because the Virtual Machine Additions install an accelerated SCSI driver. Once this driver is installed the performance of the emulated SCSI controllers is significantly faster than emulated IDE controllers.
This post is related to the issue what we faced today when we replaced the SSL certificates in our setup. When I launched the web-client and access the update manager tab, I get the message "interface
com.vmware.vim.binding.integrity.VcIntegrity is not visible from class
I started off by
restarting the VMWare vSphere Update Manager Service for the affected vCSA: 1. Log into vCenter
using the firstname.lastname@example.org account. 2. Home - System
Configuration - Services - Restart
This did not resolve
my issue... And we tried restarting all the services by SSH/Console into the
affected server and run the following commands: service-control
--start --all Still no luck. Make sure the certs are applied and it gets reflected in the config file. ( verify if the thumbprint matches) root@homelab71 [
/usr/lib/vmware-updatemgr/bin ]# pwd/usr/lib/vmware-updatemgr/bin root@homelab71 [
/usr/lib/vmware-updatemgr/bin ]# ./updatemgr-util config -g | less
Before a running virtual machine can be migrated from one host to another there are some mandatory requirements that must first be met:
Hyper-V 2008 R2 must be deployed on both hosts. The first version of Hyper-V does not support live migration.
Source and destination Hyper-V hosts must be configured as a Failover cluster with shared storage enabled.
Source and destination systems must be using shared storage (i.e. via SAN or iSCSI configurations)
Source and destination systems must be running processors from the same manufacturer. It is not, for example, possible to migrate a virtual machine from an Intel based host to one containing an AMD CPU.
The virtual machine on which the migration is to be performed must be configured as Highly Available and to use Cluster Shared Volumes.
The virtual machine's Automatic Start Action setting must be set to do Nothing.
All Hyper-V hosts in the Failover cluster must be configured to boo…