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hi everybody
I'm very new to IT field can anybody explain me relation between virtual machine and cloud computing .
In my firm they using a private cloud using ubuntu eucalyptus tool . They uses KVM.
when ever i demand the resource they says we will give u the virtual machine is cloud computing means providing virtual machine as i study cloud computing over the net it sound like a different technology .
More important i want to know does the specification(characteristic ) of virtual machine depend on the physical machine ?
which they are imitating or we can provide our specification such as making a virtual machine of 100 GB storage while the physical machine has only 20 GB hard disk?or is it possible to make a virtual machine a virtual machine 0f 4 gb RAM while physical machine is having ram of 128 mb
please explain me this concept I'll be thankful to all of you forever
Here it is in a nutshell:
A cloud is built up of numerous physical machines (the hardware). Each of these machines then run multiple virtual machines, which is what are presented to the end-users.
Virtual machines are only limited in the way that their specifications cannot exceed that of their host (the underlying physical machine).
So no, if the physical machine on which your virtual machine runs only has 20GB of harddrive space, you cannot ask them to create a VM with 100GB of disk space. (The same applies to RAM).
That being said, the way storage works on the EC2 (Amazon Compute Cloud) is a bit different. The storage is done offline, so in that case it would be possible to request drive space that exceeds the host, but again not exceeding the physical size of the actual place where the storage is done.
Furthermore, the restriction placed that Vitrual Machines cannot exceed the host capabilities also applies if you have multiple VMs running on the same host. In that case, the shared capabilities of the VMs cannot exceed that of the host. For example, if you have 4GB of RAM on the physical machine, then you can have 2 VMs each with 2GB of RAM.
Virtual machines means sharing the resources of a single physical computer among several different virtual computing environments - effectively, one computer pretending to be several computers. Obviously, you can only share whatever physical resources you have so if the physical machine has 12Gb of RAM, then you could have virtual machines that use up to 12Gb combined; however, you could distribute the 12Gb as you like, for example with one computer having 4Gb while the rest only have 1Gb. Similarly with hard disk space and processing power.
Cloud computing is effectively many computers pretending to be the one computing environment. In practice, the computers making up the cloud system will also be virtualised in order to maximise the resources of the physical computers.
Related
I was studying VMWare's VSphere suite, cloud computing virtualization platform.
I could not figure out whether there's any relation between VMotion and VMFS in the suite?
VMotion enables the live migration of running virtual machines from
one physical server to another with zero down time.
VMFS is a clustered file system that leverages shared storage to allow multiple physical hosts to read and write to the same storage simultaneously.
Is there any relation between them?
No.
As you mention, VMFS is the file system we use by default on "block" shared storage (i.e. LUNs). This allows us to have the same LUN mounted for read/write on multiple ESXi hosts which is not allowed with many file systems.
vMotion is when we move a running VM from one ESXi host to another. We do this by copying the running memory state from one host to another. When then "stun" the VM for a short period of time and quickly move it's virtual NIC to the new server. The VM "starts" on the far side in the same state, thus it appears like the VM has always been running. That is to say we "move" the running VM even though we are actually just creating a new VM with exactly the same memory state and disk.
The only relationship is that if you have a VM whose VMDKs live in a Datastore which is shared across multiple ESXi hosts, the vMotion process doesn't have to copy the VMDK which makes the process much simpler and faster. Since VMFS is one way we can support shared storage, it is common to have VMDK's on VMFS based datastores (in this case 1 datastore = one VMFS formatted LUN). Since VMFS is our oldest shared storage technology, it's the most common and usually be best understood by our customers.
However, any shared storage will work just fine for vMotion, including VSAN, VVOL and NFS based shared storage.
As a very beginner, I only know how to create VMs and install OS on these using Oracle VirtualBox. All the VMs created are dependent on the hardware resources (CPU, RAM etc.) of a single machine. If the machine goes down the VMs will go down. Need to know how VMs can be created using taking resources from different physical machines (manually or dynamically) to avoid failure of any VMs.
For example: There are 4 physical machines having 8 core and 16GB RAM each. Now, I want to create three VM having having 8 core and 16GB RAM taking from different physical machines. If one physical machine goes down, no VM will be down.
You can look up clustering solutions (e.g. VMware clusters, or Hyper-V failover clusters). In this model, if a physical host goes down, then the virtualization platform will power up the VMs on other hosts.
If you're looking for zero downtime, then VMware has something called Fault Tolerance in which a shadow copy of a VM is running on a different host and is continuously synchronized with the primary copy. If the primary host goes down, the shadow copy can take over with zero downtime (e.g. you don't have to boot from the shadow copy because it's already running). This feature, while cool, has a lot of real-world limitations in how it inter-operates with other features of VMware. For example, as of vSphere 6.0, you cannot do various kinds of migrations for such VMs, etc. I believe it also requires a more expensive license.
These solutions generally require some shared resources between the physical hosts (most notably storage). Otherwise they will not work (or at the very least, performance will greatly suffer).
Is it possible to "mount" a virtual machine located in the cloud to my computer? Or in other terms to pipe some threads directly from my machine to the cloud and get the results back to virtually improve my computer's power.
I searched something existing with virtual machines or docker but I didn't find anything.
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I am installing virtual box on my window
I will use it for anonymous web browsing and nothing else.
I will also install ccleaner on the VM.
The total Amount is 2GB.
How much ram should I put on my Virtual Machine?
Which version of window is the best for Anonymous Web Browsing?
Is linux a better option for anonymity web browsing?
Though i agree with above comments, it doesn't hurt to add some info. I take that you mean you have 2GB Ram in total.
First, the amount of ram required is proportional to how much you actually use it(VM) for and whether will you be using your primary machine in parallel or not.
For e.g. i have a 64 bit system windows 7 with 8 GB ram. I frequently use 1 linux VM in parallel with my host machine. So i have dedicated 2GB per VM. Though i have multiple VM's, it is almost guaranteed that i don't use two VM's simultaneously. However, i am extensively using VM + host together.
Now if you are going to do a lot of browsing, that probably means a lot of tabs, perhaps including you tube videos and stuff. Since your total is 2GB, i won't recommended allocating more than 512MB to your VM, unless you are willing to sacrifice your host performance for the time you are running VM.
Anonymous browsing has little to do with OS rather more important is browser or intermediate application. The only possible difference is for e.g. if you are using Linux and use an open source application such as
tor
which may or may not be available on windows. [Edit: just verified that tor does exist on windows too]
CCleaner is of no use if you are already using a common feature of FF/Ch/IE "Start private browsing". However, this does not leave any thing in your history and cache.
I also believe you are some what confusing anonymous browsing. Use of VM or CCcleaner refers to anonymity which is local to your machine i.e. if some one else uses your pc, he/she would not be able to track what you have been doing by ordinary means.
However, your real ip and request info is not hidden from your network in general. Using of Tor or some proxies etc. results in network anonymity where you leave no trace on a site which you have visited or perhaps that is blocked in your region.
Another thing is, if you have a 32bit machine / OS which is windows, it doesn't utilize more than 3GB ram in practice.
regarding ram: 0.5 gb should be enough but in any case virtual box recomends those values when you telling it what you about to install on the vm.
Windows 7 is best os I seen comming out from MS house till today especially in security.
IE9 private browsing can do what you ask for without a vm at all.
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I find myself wasting more and more time the last few years when I have to reinstall an OS and 20+ development tools and apps. I'm looking to do more work in virtual machines.
Now that you are starting to see 32GB and 64GB thumb drives. I was wondering can you run a Virtual PC or VMWare image from a USB Thumb drive? Any issues with doing this? I would plan on backing up the image daily just in case something happened to the drive.
Running a VM off a flash drive would have positively putrid performance. I guess you could copy the virtual hard drive to local storage first, though. I run my VMs off an external hard drive, myself.
I suggest you invest in an external SSD to put those VMs on. Thumb drives are not known for speed.
This is entirely doable. Take a look at VMware Player -- To Go. Performance will be worse than an internal hard drive but not completely terrible. Jeff did a brief comparison.
I've never tried a thumb drive, but I use external USB drives for virtual machines all the time. I use VirtualPC 2007 and have had no problems. In fact, sometimes if the host machine is on the weaker side, having the VM on an external drive increases performance. I recommend the external USB drive route.
Windows XP (and Vista and 7) can boot on multiple hardware configurations, each with different drivers (retail license, not OEM).
I started out with a 2.5" USB HDD for my portable enviroment. It was booting fine on multiple machines (#home, #work, or in any VMWare).
I don't recommend a flash stick, but I do recommend a SSD stick. Today you can find SSD sticks with 2 ends, one USB and one eSATA.
For booting USB drives with Windows XP you need USBoot.
After booting the first time, Windows will install some drivers, including the Disk Controller drivers (without which, if booting directly on SATA Windows would BSOD with 0x0000007b).
Since the first Intel SSD came out, I switched to using a SSD.
I have 2 2.5" trays (insert 2.5" drive like a floppy) both #home and #work.
I can boot that Windows in VMWare and on many other computers using USB (and I have, and it was life saving). I even booted from the backup VHD once :)
I use Windows Backup to backup to a versioned VHD (in command line, see wbadmin command on Windows Vista, 7, 2008, 2008 R2).
I can restore the entire enviroment including the OS pretty fast, and I have recovered from several disasters.
I also use EFS for important files (don't forget to backup your EFS files).
I pretty much have the smallest laptop arround, and I am very happy I don't have to carry a laptop bag back and forth to my workplace.
USBoot should work with Windows Vista and 7, yet I haven't had the time to switch (time consuming process for the size and complexity of my stuff).