Snapshots and cloning summary of VMware

Introduction to multiple snapshots features:

The meaning of a snapshot: a mirror with a read-only property for a particular filesystem at a specific time. When you need to return to a system state repeatedly and do not want to create more than one virtual machine, you can use the snapshot feature. In fact, snapshots are not a new feature of VMware Workstation 5. In the era of VMware Workstation 4, snapshot functionality has been supported. But VMware Workstation 4 can only generate one snapshot, that is, VMware Workstation 4 creates only two states: the current state and the snapshot state. It's not flexible enough to use. In contrast, VMware Workstation 5 and other upgraded versions of the multiple snapshots feature are really powerful. New multiple snapshots, which can create more than two snapshots for a single virtual machine, which means that we can make multiple snapshots of the system environment at different times, and go back and forth between any snapshots without restriction. At the same time, the snapshot Manager provides the image of the relationship between multiple snapshot mirrors of VMware. The tree-like structure allows us to easily browse and use the generated snapshots. So what does the new snapshot feature do for us? In fact, multiple snapshots do not simply save multiple states of a virtual machine, by creating multiple snapshots, you can save multiple states for different jobs and do not interact with each other. For example, when we do experiments or test on a virtual machine, unavoidably encounter some unfamiliar place, at this time make a snapshot, back up the current system state, once the operation error, can quickly revert to the state before the error, complete the experiment, and ultimately avoid a step of the error leading to restart the whole experiment or test the consequences.

To create a snapshot specific steps:

1. Start a virtual machine, click VM to expand Snapshot (Snapshot) in the menu, click Take Snapshot ... (Create a snapshot of the current state of the bundle)

2. In the Create Snapshot window, fill in the name and comment of the snapshot, and click OK.

what is cloning.

Said the snapshot, then, what is the virtual machine cloning it. In VMware software, cloning and snapshot functions are very similar, but different, slightly less attention will be confusing. A clone of a virtual machine is a copy of the entire state of the original virtual machine, or a mirror. The cloning process does not affect the original virtual machine, cloning operations once completed, the cloned virtual machine can be isolated from the original virtual machine, and in the cloned virtual machine and the original virtual machine operations are relatively independent, do not affect each other. During the cloning process, VMware generates a different MAC address and UUID from the original virtual machine, which allows the cloned virtual machine and the original virtual machine to appear on the same network without any conflicts. VMware supports two types of clones: Full clone link clone

A complete clone is a completely independent copy of the original virtual machine, and it does not share any resources with the original virtual machine. Can be used independently from the original virtual machine.

A linked clone needs to share the same virtual disk file with the original virtual machine and cannot run independently from the original virtual machine. However, the use of shared disk files greatly reduces the time it takes to create a cloned virtual machine, while also saving valuable physical disk space. By linking clones, you can easily create a separate virtual machine for different tasks.

to create a cloned virtual machine :

1. Open a virtual machine and click the Clone this virtual machine (clone the VM) button.

Note: The clone virtual machine can only be performed in a state where the virtual machine is not started.

2. On the Clone Virtual Machine Creation Wizard page, click Next.

3. Choose to create a clone from the current state or a snapshot.

As you can see, the cloning process can operate either according to the current state of the virtual machine, or mirroring the image of a cloned clone that already exists or a snapshot.

4. On the Clone Type Selection page, you can choose the type of clone virtual machine you created "linked Clone (Contact clone)" or "Full clone". A connected clone points to the original virtual machine, takes up very little disk space, but relies on the original virtual machine and cannot run independently from the original virtual machine. A complete

Clones provide a copy of the current state of the original virtual machine, which can run independently, but takes up a lot of disk space.

Here we select Create a linked clone (create linked clones) and click Next.

5, fill in the name of the cloned virtual machine on the new virtual machine Name page, and determine the installation location of the new virtual machine.

6, click Finish, complete the establishment of new clones. In the same way, we can create clones of multiple virtual machines.

the difference between a snapshot and a clone :

Say so much, in order to let everybody clearer understanding the difference between snapshot and clone, we may as well make a table, summarize.

Snapshot Cloning

Creation time: not limited to Virtual body machine

Create Quantity: Unlimited

Disk space consumption: determined by the number of created, the smaller the number of created, the larger the complete clone

Purpose: Save virtual machine for a moment state distribution created by a virtual machine

Independent: Cannot run a linked clone independently from the original virtual machine: partially detached from full clone: completely detached from

can be used simultaneously: a virtual machine that cannot be cloned may be used concurrently with the original virtual machine

Network usage: cannot generate different MAC addresses and UUID from the original virtual machine, which can be used simultaneously in the network

Management of mirroring:

Both snapshots and clones generate a mirror image of a state of the virtual machine, whether it exists as part of the virtual machine or as an independent part. In short, we can create multiple mirrors from VMware to hold the virtual machines in different time states. How do we manage so many mirrors? Let's take a look at our results from the snapshot manager below.

VMware provides a snapshot manager for managing mirroring and snapshots. In the snapshot manager, the snapshot tree image displays the hierarchy of the current multiple snapshots. Clicking to manage any one of these mirrors will give you an image name for the mirror, write the necessary comments, delete the snapshot, and create a new clone based on the selected snapshot. With the snapshot manager, it is easy to manage the snapshot.