Jovan Stosic
Pentium D support VT Technology.
Source: Enable VT on 745 for 64 bit virtual machines – Dell Community
Jovan Stosic
I have been converting some of my old VirtualBox images to KVM, which is the virtualization standard in Linux.
Its really easy, although, if you run into booting issues of the converted image, the last tip here will save you some time.
To convert from VirtualBox to KVM, look for your VDI images.
qemu-img convert -f vdi -O qcow2 [VBOX-IMAGE.vdi] [KVM-IMAGE.qcow2]
e.g. qemu-img convert -f vdi -O qcow2 FreeBSD-7.2.vdi FreeBSD-7.2.qcow2
You can now import the converted image using virt-manager or the CLI tool virt-install.
In Virtual Machine Manager, go to Disk 1 >> Advanced options and change ‘Storage format’ to qcow2.
This prevents boot errors like ‘boot failed: not a bootable disk’ when you launch the VM.
Source: Easily convert from VirtualBox to KVM in Linux – Joseph Zikusooka Joseph Zikusooka
Jovan Stosic
Type 1 hypervisors:
1. VMware ESX and ESXi
These hypervisors offer advanced features and scalability, but require licensing, so the costs are higher.
There are some lower-cost bundles that VMware offers and they can make hypervisor technology more affordable for small infrastructures.
VMware is the leader in the Type-1 hypervisors. Their vSphere/ESXi product is available in a free edition and 5 commercial editions.
2. Microsoft Hyper-V
The Microsoft hypervisor, Hyper-V doesn’t offer many of the advanced features that VMware’s products provide.
However, with XenServer and vSphere, Hyper-V is one of the top 3 Type-1 hypervisors.
It was first released with Windows Server, but now Hyper-V has been greatly enhanced with Windows Server 2012 Hyper-V. Hyper-V is available in both a free edition (with no GUI and no virtualization rights) and 4 commercial editions – Foundations (OEM only), Essentials, Standard, and Datacenter. Hyper-V
3. Citrix XenServer
It began as an open source project.
The core hypervisor technology is free, but like VMware’s free ESXi, it has almost no advanced features.
Xen is a type-1 bare-metal hypervisor. Just as Red Hat Enterprise Virtualization uses KVM, Citrix uses Xen in the commercial XenServer.
Today, the Xen open source projects and community are at Xen.org. Today, XenServer is a commercial type-1 hypervisor solution from Citrix, offered in 4 editions. Confusingly, Citrix has also branded their other proprietary solutions like XenApp and XenDesktop with the Xen name.
4. Oracle VM
The Oracle hypervisor is based on the open source Xen.
However, if you need hypervisor support and product updates, it will cost you.
Oracle VM lacks many of the advanced features found in other bare-metal virtualization hypervisors.
Type 2 hypervisor
1. VMware Workstation/Fusion/Player
VMware Player is a free virtualization hypervisor.
It is intended to run only one virtual machine (VM) and does not allow creating VMs.
VMware Workstation is a more robust hypervisor with some advanced features, such as record-and-replay and VM snapshot support.
VMware Workstation has three major use cases:
for running multiple different operating systems or versions of one OS on one desktop,
for developers that need sandbox environments and snapshots, or
for labs and demonstration purposes.
2. VMware Server
VMware Server is a free, hosted virtualization hypervisor that’s very similar to the VMware Workstation.
VMware has halted development on Server since 2009
3. Microsoft Virtual PC
This is the latest Microsoft’s version of this hypervisor technology, Windows Virtual PC and runs only on Windows 7 and supports only Windows operating systems running on it.
4. Oracle VM VirtualBox
VirtualBox hypervisor technology provides reasonable performance and features if you want to virtualize on a budget. Despite being a free, hosted product with a very small footprint, VirtualBox shares many features with VMware vSphere and Microsoft Hyper-V.
5. Red Hat Enterprise Virtualization
Red Hat’s Kernel-based Virtual Machine (KVM) has qualities of both a hosted and a bare-metal virtualization hypervisor. It can turn the Linux kernel itself into a hypervisor so the VMs have direct access to the physical hardware.
KVM
This is a virtualization infrastructure for the Linux kernel. It supports native virtualization on processors with hardware virtualization extensions.
The open-source KVM (or Kernel-Based Virtual Machine) is a Linux-based type-1 hypervisor that can be added to most Linux operating systems including Ubuntu, Debian, SUSE, and Red Hat Enterprise Linux, but also Solaris, and Windows.
VirtualBo
Source: What is Hypervisor and what types of hypervisors are there?
Jovan Stosic
Previously codenamed “Vanderpool”, VT-x represents Intel’s technology for virtualization on the x86 platform. On November 13, 2005, Intel released two models of Pentium 4 (Model 662 and 672) as the first Intel processors to support VT-x. The CPU flag for VT-x capability is “vmx”; in Linux, this can be checked via /proc/cpuinfo, or in macOS via sysctl machdep.cpu.features.[19]
“vmx” stands for Virtual Machine Extensions, which adds ten new instructions: VMPTRLD, VMPTRST, VMCLEAR, VMREAD, VMWRITE, VMCALL, VMLAUNCH, VMRESUME, VMXOFF, and VMXON.[20] These instructions permit entering and exiting a virtual execution mode where the guest OS perceives itself as running with full privilege (ring 0), but the host OS remains protected.
As of 2015, almost all newer server, desktop and mobile Intel processors support VT-x, with some of the Intel Atom processors as the primary exception.[21] With some motherboards, users must enable Intel’s VT-x feature in the BIOS setup before applications can make use of it.
Intel started to include Extended Page Tables (EPT),a technology for page-table virtualization,[24] since the Nehalem architecture, released in 2008. In 2010, Westmere added support for launching the logical processor directly in real mode – a feature called “unrestricted guest”, which requires EPT to work.[27][28]
Since the Haswell microarchitecture (announced in 2013), Intel started to include VMCS shadowing as a technology that accelerates nested virtualization of VMMs.[29] The virtual machine control structure (VMCS) is a data structure in memory that exists exactly once per VM, while it is managed by the VMM. With every change of the execution context between different VMs, the VMCS is restored for the current VM, defining the state of the VM’s virtual processor.[30] As soon as more than one VMM or nested VMMs are used, a problem appears in a way similar to what required shadow page table management to be invented, as described above. In such cases, VMCS needs to be shadowed multiple times (in case of nesting) and partially implemented in software in case there is no hardware support by the processor. To make shadow VMCS handling more efficient, Intel implemented hardware support for VMCS shadowing.
Source: x86 virtualization – Wikipedia
Jovan Stosic
The Epic of Gilgamesh (/ˈɡɪlɡəmɛʃ/) is an epic poem from ancient Mesopotamia that is often regarded as the earliest surviving great work of literature. The literary history of Gilgamesh begins with five Sumerian poems about Bilgamesh (Sumerian for “Gilgamesh”), king of Uruk, dating from the Third Dynasty of Ur ( 2100 BC). These independent stories were later used as source material for a combined epic in Akkadian. The first surviving version of this combined epic, known as the “Old Babylonian” version, compiled by Sîn-lēqi-unninni, dates to the 18th century BC and is titled after its incipit, Shūtur eli sharrī (“Surpassing All Other Kings”). Only a few tablets of it have survived. The later “standard” version dates from the 13th to the 10th centuries BC and bears the incipit Sha naqba īmuru (“He who Saw the Abyss”, in modern terms: “He who Sees the Unknown”). Approximately two thirds of this longer, twelve-tablet version have been recovered. Some of the best copies were discovered in the library ruins of the 7th-century BC Assyrian king Ashurbanipal.
Jovan Stosic
Andrew “Tridge” Tridgell (born 28 February 1967) is an Australian computer programmer. He is the author of and a contributor to the Samba file server, and co-inventor of the rsync algorithm.
He has analysed complex proprietary protocols and algorithms, to allow compatible free and open source software implementations.
Source: Andrew Tridgell – Wikipedia
Jovan Stosic
The Firebird (French: L’Oiseau de feu; Russian: Жар-птица, translit. Zhar-ptitsa) is a ballet and orchestral concert work by the Russian composer Igor Stravinsky. It was written for the 1910 Paris season of Sergei Diaghilev‘s Ballets Russes company; the original choreography was by Michel Fokine, with a scenario by Alexandre Benois and Fokine based on the Russian fairy tales of the Firebird and the blessing and curse it possesses for its owner. When first performed at the Opéra de Paris on 25 June 1910, the work was an instant success with both audience and critics.
The ballet has historic significance not only as Stravinsky’s breakthrough piece, but also as the beginning of the collaboration between Diaghilev and Stravinsky that would also produce the acclaimed ballets Petrushka (1911) and The Rite of Spring (1913).
Source: The Firebird – Wikipedia
Jovan Stosic
Jovan Stosic
Jovan Stosic
The Great Courses (TGC) is a series of college-level audio and video courses produced and distributed by The Teaching Company, an American company based in Chantilly, Virginia.
Jovan Stosic