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Implement and configure AWS Backup for VMware Cloud on AWS VM workloads

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In our previous post we saw the design of the AWS Backup on VMC. In this post we’re going through the implementation steps As per the design and best practice, we are going to use the ENI for the Backup traffic CREATE A VPC ENDPOINT  TO CREATE AN INTERFACE ENDPOINT FOR AN AWS SERVICE 1. Open the Amazon VPC console at https://console.aws.amazon.com/vpc    2. In the navigation pane, choose Endpoints 3. Choose Create endpoint 4. Name the endpoint   5. For Service category, choose AWS services 6. For Service name, search “ Backup ” and select “ backup-gateway ” service from the dropdown 7. For VPC, select the VPC which we used for SDDC deployment and extension 8. To create an interface endpoint for Amazon S3, you must “uncheck” Additional settings, Enable DNS name. This is because Amazon S3 does not support private DNS for interface VPC endpoints 9. For  Subnets , select one subnet per Availability Zone which we used for SDDC VMC selection  10. For Security group , sel

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.

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