22 days to go..Reverse counter starts for Existing VCP :)
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Snapshot Files
A snapshot consists of files that are stored on a supported storage device. A Take Snapshot operation creates .vmdk, -flat.vmdk, .vmsd, and .vmsn files. By default, the first and all subsequent snapshots are stored with the virtual machine base files.
Delta Disks
A delta disk has two files, including a descriptor file that is small and contains information about the virtual disk, such as geometry and child-parent relationship information, and a corresponding file that contains the raw data.
NOTE If you are looking at a datastore with the Datastore Browser in the vSphere Client, you see only one entry to represent both files.
In above figure you can see 000002–delta.vmdk is bigger in size compared to 000002.vmdk file
The files that make up the delta disk are referred to as child disks or redo logs.A child disk is a sparse disk. Sparse disks use the copy-on-write mechanism, in which the virtual disk contains no data in places, until copied there by a write operation. This optimization saves storage space. A grain is the unit of measure in which the sparse disk uses the copy-on-write mechanism. Each grain is ablock of sectors that contain virtual disk data. The default size is 128 sectors or 64 KB.
Database file (vmsd)
A .vmsd file that contains the virtual machine’s snapshot information and is the primary source of information for the Snapshot Manager. This file contains line entries, which define the relationships between snapshots and between child disks for each snapshot.
.vmsd file contents grabbed from putty
Memory file(.vmsn)
A .vmsn file that includes the active state of the virtual machine. Capturing the memory state of the virtual machine lets you revert to a turned on virtual machine state. With non-memory snapshots, you can only revert to a turned off virtual machine state. Memory snapshots take longer to create than non-memory snapshots. The time the ESX host takes to write the memory on to the disk is relative to the amount of memory the virtual machine is configured to use.
In above figure two snapshots are created.
Using Snapshots To Manage Virtual Machines
Snapshots are useful as a short term solution for testing software with unknown or potentially harmful effects.For example, you can use a snapshot as a restoration point during a linear or iterative process, such as installing update packages, or during a branching process, such as installing different versions of a program.
Using snapshots ensures that each installation begins from an identical baseline.With snapshots, you can preserve a baseline before diverging a virtual machine in the snapshot tree.
The Snapshot Manager in the vSphere Web Client and the vSphere Client provide several operations for creating and managing virtual machine snapshots and snapshot trees. These operations let you create snapshots, restore any snapshot in the snapshot hierarchy, delete snapshots, and more. You can create extensive snapshot trees that you can use to save the virtual machine state at any specific time and restore the virtual machine state later. Each branch in a snapshot tree can have up to 32 snapshots.
A snapshot preserves the following information:
· Virtual machine settings. The virtual machine directory, which includes disks that were added or changed after you took the snapshot.
· Power state. The virtual machine can be powered on, powered off, or suspended.
· Disk state. State of all the virtual machine’s virtual disks.
· (Optional) Memory state. The contents of the virtual machine’s memory.
The Snapshot Hierarchy
The Snapshot Manager presents the snapshot hierarchy as a tree with one or more branches. The relationship between snapshots is like that of a parent to a child. In the linear process, each snapshot has one parent snapshot and one child snapshot, except for the last snapshot, which has no child snapshots. Each parent snapshot can have more than one child. You can revert to the current parent snapshot or restore any parent or child snapshot in the snapshot tree and create more snapshots from that snapshot. Each time you restore a snapshot and take another snapshot, a branch, or child snapshot, is created.
Parent Snapshots The first virtual machine snapshot that you create is the base parent snapshot.The parent snapshot is the most recently saved version of the current state of the virtual machine. Taking a snapshot creates a delta disk file for each disk attached to the virtual machine and optionally, a memory file. The delta disk files and memory file are stored with the virtual machine’s files. The parent snapshot is always the snapshot that appears immediately above the You are here icon in the Snapshot Manager. If you revert or restore a snapshot, that snapshot becomes the parent of the You are here current state.
No snapshot is taken in above screen.
Screen capture while taking snapshot
After snapshot is taken
Child Snapshots A snapshot that is taken of the same virtual machine after the parent snapshot.Each child constitutes delta files for each attached virtual disk, and optionally a memory file that points from the present state of the virtual disk (You are here). Each child snapshot’s delta files merge with each previous child snapshot until reaching the parent disks. A child disk can later be a parent disk for future child disks.The relationship of parent and child snapshots can change if you have multiple branches in the snapshot tree.
IMPORTANT Do not manually manipulate individual child disks or any of the snapshot configuration files because doing so can compromise the snapshot tree and result in data loss. This restriction includes disk resizing and making modifications to the base parent disk using vmkfstools.
Each snapshot creates an additional delta .vmdk disk file. When you take a snapshot, the snapshot mechanism prevents the guest operating system from writing to the base .vmdk file and instead directs all writes to the delta disk file. The delta disk represents the difference between the current state of the virtual disk and the state that existed at the time that you took the previous snapshot. If more than one snapshot exists, delta disk scan represent the difference between each snapshot.
Warning Delta disk files can expand quickly and become as large as the entire virtual disk if the guest operating system writes to every block of the virtual disk.
How To Open a Virtual Machine Console in the vSphere Web Client
With the vSphere Web Client, you can access a virtual machine’s desktop by launching a console to the virtualmachine. From the console, you can perform activities in the virtual machine such as configure operatingsystem settings, run applications, monitor performance, and so on.
Prerequisites
n Ensure that the Client Integration Plug-in is installed in your Web browser.
n Verify that the virtual machine has a guest operating system and that VMware Tools are installed.
n Verify that the virtual machine is powered on.
Pop blocker is disabled
Procedure
1 Select a virtual machine.
2 In the Guest OS Details pane on the Summary tab, click Launch console.
The virtual machine console opens in a new tab of the Web browser.
3 Click anywhere inside the console window to enable your mouse, keyboard, and other input devices to work in the console.
4 (Optional) Press Ctrl+Alt to release the cursor from the console window and work outside the console window.
5 (Optional) Click Full Screen to display the console in full screen mode.
6 (Optional) Press Ctrl+Alt+Enter to exit full screen mode.
7 (Optional) Click Send Ctrl-Alt-Delete to send a Ctrl+Alt+Delete to the guest operating system.
Edit Virtual Machine Startup and Shutdown Settings
You can configure virtual machines running on an ESXi host to start up and shut down with the host. You can also set the default timing and startup order for selected virtual machines. This ability allows the operating system to save data when the host enters maintenance mode or is being powered off for another reason. This setting is disabled when DRS cluster is enabled.
Procedure
1. In the vSphere Client inventory, select the host where the virtual machine is located and click the Configuration tab.
2. Under Software, click Virtual Machine Startup/Shutdown and click Properties.
The Virtual Machine Startup and Shutdown dialog box opens.
3. Select Allow virtual machines to start and stop automatically with the system.
Power on a vApp
Each virtual machine within the vApp is powered on according to the startup order configuration. When powering on a vApp within a DRS cluster in manual mode, no DRS recommendations are generated
for virtual machine placements. The power-on operation performs as if DRS is run in a semiautomatic or
automatic mode for the initial placements of the virtual machines. This does not affect vMotion
recommendations. Recommendations for individual powering on and powering off of virtual machines are
also generated for vApps that are running.
Prerequisites
Required privilege: vApp.Power On on the vApp.
Procedure
Right-click the vApp and select Power > Power On.
In the Summary tab, the Status portlet indicates when the vApp has started and is available.
Required privilege to Power Off vApp: vApp.Power Off on the vApp.
Required privilege to Power Off vApp: vApp.Suspend on the vApp.
Configuring IP Pools in vApps
IP pools provide a network identity to vApps. An IP pool is a network configuration that is assigned to a network used by a vApp. The vApp can then leverage vCenter Server to automatically provide an IP configuration to its virtual machines.
Specify an IP Address Range
You can set up an IP address range by specifying a host address range within a network. IP pool ranges are configured with IPv4 and IPv6. vCenter Server uses these ranges to dynamically allocate IP addresses to virtual machines when a vApp is set up to use transient IP allocation.
Procedure
1. In the inventory, select the datacenter that contains the vApp.
2. In the IP Pools tab, right-click the IP pool that you want to edit and select Properties.
If no IP pools appear, click Add to add a new IP pool.
6. (Optional) Enter a comma-separated list of host address ranges in the Ranges field.
A range consists of an IP address, a pound sign (#), and a number indicating the length of the range. The gateway and the ranges must be within the subnet, but must exclude the gateway address. For example, 10.20.60.4#10, 10.20.61.0#2 indicates that the IPv4 addresses can range from 10.20.60.4 to 10.209.60.13 and 10.20.61.0 to 10.20.61.1.
2. Click OK.
Select DHCP
You can specify that an IPv4 or IPv6 DHCP server is available on the network.
Procedure
1. In the inventory, select the datacenter that contains the vApp you are configuring.
2. In the IP Pools tab, right-click the IP pool that you want to edit and select Properties.
If no IP pools appear, click Add to add a new IP pool.
3. In the Properties dialog box, select the DHCP tab.
4. Select either the IPv4 DHCP Present or IPv6 DHCP Present check box to indicate that one of the DHCP servers is available on this network.
Specify DNS Settings
Enter the DNS settings for the vApp.
Procedure
1. In the inventory, select the datacenter that contains the vApp you are configuring.
2. In the IP Pools tab, right-click the IP pool that you want to edit and select Properties.
3. If no IP pools appear, click Add to add a new IP pool.
In the Properties dialog box, select the DNS tab.
4. Enter the DNS server information.
Specify the servers by IP addresses separated by a comma, semicolon, or space.
You can enter the following types of DNS information:
a. DNS Domain
b. Host Prefix
c. DNS Search Path
d. IPv4 DNS Servers
e. IPv6 DNS Servers
5. Click OK.
Specify a Proxy Server
Specify a HTTP proxy server for the vApp.
Procedure
1. In the inventory, select the datacenter that contains the vApp.
2. In the IP Pools tab, right-click the IP pool that you want to edit and select Properties.
If no IP pools appear, click Add to add a new IP pool.
3. In the Properties dialog box, select the Proxy tab.
4. Enter the server name and port number for the proxy server.
The server name can optionally include a colon and a port number.
For example, web-proxy:3912 is a valid proxy server.
5. Click OK.
Select Network Associations
You can associate one or more networks with an IP pool.
Procedure
1. In the inventory, select the datacenter that contains the vApp.
2. In the IP Pools tab, right-click the IP pool that you want to edit and select Properties.
If no IP pools appear, click Add to add a new IP pool.
3. In the Properties dialog box, select the Associations tab.
4. Select the networks that use this IP pool.
A network can be associated with one IP pool at a time.
5. Click OK.
Edit Advanced IP Allocation Properties (Not possible from WebClient)
You can edit the IP allocation scheme for the vApp.
Procedure
1. On the Summary page of the vApp, click Edit Settings.
2. Click Advanced in the Options tab.
3. Click IP Allocation.
1. In the Advanced IP Allocation dialog box, you can perform the following actions.
a. Select an IP allocation Scheme.
b. Select the IP protocols supported by the vApp: IPv4, IPv6, or both.
Click OK
Configure vApp using vSphere Web Client
Configure vApp Startup and Shutdown Options in the vSphere Web Client
You can change the order in which virtual machines and nested vApps within a vApp start up and shut down.You can also specify delays and actions performed at startup and shutdown.
Prerequisites
Required privilege: vApp.vApp application configuration on the vApp.
Procedure
1. Right-click the vApp in the inventory and select Configuration > Edit Settings.
2. Click the Start Order triangle to expand the start order options.
3. Select a virtual machine and click the up or down arrow to move the virtual machine in the startup order. Virtual machines and vApps in the same group will start concurrently with each other. The reverse order will be used for shutdown.
4. For each virtual machine, select the startup action for the virtual machine.
5. (Optional) Set the delay for the startup action.
a. Enter a time delay in seconds for the startup action.
b. Select VMware Tools are ready to perform the startup action when VMware Tools has started.
6. For each virtual machine, select the shutdown action for the virtual machine.
7. (Optional) Enter a time delay in seconds for the shutdown action.
8. Click OK.
Configure vApp Product Properties in the vSphere Web Client
Procedure
Right-click the vApp in the inventory and select Configuration > Edit Settings.
Click the Product triangle to expand the product options.
Set and configure the settings that appear on the summary page of the virtual machine.

