No matter how sophisticated the technology is , It still takes people !
Subscribe to this blog
Follow by Email
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.
1. Create and AD LDS instance by clicking Start -> Administrative Tools -> Active Directory Lightweight Directory Services Setup Wizard. The Setup Wizard appears. 2. Click Next. The Setup Options dialog box appears. For the sake of this guide, a unique instance will be the primary focus. I will have a separate post regarding AD LDS replication at some point in the near future. 3. Select A unique instance. 4. Click Next and the Instance Name dialog box appears. The instance name will help you identify and differentiate it from other instances that you may have installed on the same end point. The instance name will be listed in the data directory for the instance as well as in the Add or Remove Programs snap-in. 5. Enter a unique instance name, for example IDG. 6. Click Next to display the Ports configuration dialog box. 7. Leave ports at their default values unless you have conflicts with the default values. 8. Click Next to display the App…
The previous post talks about vSphere Integrated Containers and their benefits. The VIC offers a robust solution that enables the vSphere environment to quickly get containers up and running in their current vSphere infrastructure. This environment can be useful for migrating current apps to containers or for in-house development. Architecture
In a traditional container environment, containers run as threads within the container host. vSphere Integrated Containers leverage the native constructs of vSphere for provisioning container-based applications into its own container running its own very minimal Linux kernel with just enough code to run a Docker image, thus preventing any issue with containers being accessed from other containers by pushing isolation of the container down to the hypervisor layer that is much better at handling this type of isolation.
What is an Inventory? An Inventory is the process of mounting media in the drive and reading the media label, which is then displayed in the Devices view. If this is the first time that Backup Exec ™ has encountered this media, the media label is also added to the Media view. Note: Each time new tape is introduced in the tape drive or robotic library, it must be inventoried so that the Backup Exec database gets updated with the new tape Information. To Inventory a Tape/Robotic Library: 1. Insert the tape 2. Click the Devices tab 3. Select the correct tape drive/robotic library slot 4. Right-click on the tape drive/robotic library slot and select Inventory (Figure 1) Figure 1
The inventory will complete and should display the correct tape name. What is a Catalog? When cataloging a tape, Backup Exec reads the header information from the tape and stores it in a file on the hard drive. The information contained in the catalog includes, but is not limited to: Tape number/label/name (something to identi…