VMware Concepts

What is VMHA?
Minimize Downtime from Server and Operating System Failures

What are the key features of VMware HA?
1) Proactive monitoring of all physical  and virtual machines 

2) Automatic detection of server failure 

3) Optimal placement of virtual machines after server failure

4) Scalable availability up to 32 nodes across multiple servers

What is VMware DRS (Distributed Resource Scheduler) ?
It is an utility that balances computing workloads with available resources.
features of VMware DRS
1)Continuous monitoring of hardware utilization 2) Downtime-free server maintenance
3) Centralized control of hardware parameters
DRS Configuration Steps:
Manual: vCenter will suggest migration recommendations for VM's

Partially Automated: VM's will be automatically placed onto hosts at power on and vCenter will  suggest migration recommendations 

Fully Automated:  VM's will be automatically placed onto hosts at power on and will be automatically migrated to attain best use of resources.

What is vMotion?

Move running virtual machines from one physical server to another with no impact to end users

What is SVmotion?
Storage VMotion relocates virtual machine disk files from one shared storage location to another shared storage location with zero downtime.

What are port Groups in ESXI

1. Virtual Machine
2. VMKernal
what is VMKernal?
It provides basic operating system services needed to support virtualization: hardware abstraction, hardware drivers, scheduler, memory allocator, filesystem (vmfs), and virtual machine monitor (vmm)

what is the use of VMKernal Port group?

Vmkernel port is used for vmotion, ISCSI & NFS communications. 

Virtual Machine Port Group?

VM port groups are a way to create logical rules around the virtual ports that are made available to VMs. It's common to create a port group for each VLAN and network subnet that you want to present to your VMs.

what is the use of Virtual Machine Port Group?
This is used by Virtual Machine communication.

What is Thin and Thick disks.
thick disk pre-allocates all of the space specified during the creation of the disk
Thin disk eliminates storage waste and the need for dedicated capacity.

what is vmdk?

Virtual machine disk is a file format used by VMware products. to store a virtual machine image and the contents of a VMware virtual machine hard disk.

What are the files that make a Virtual Machine  ? 

     .vmx - Virtual Machine Configuration File 

     .nvram - Virtual Machine BIOS 

     .vmdk - Virtual Machine Disk file 

     .vswp - Virtual Machine Swap File 

     .vmsd - Virtual MAchine Snapshot Database 

     .vmsn - Virtual Machine Snapshot file 

     .vmss - Virtual Machine Suspended State file 

     .vmware.log - Current Log File 

     .vmware-#.log - Old Log file

Benefits of VMFS?

• Automated Cluster File System Capability

• Optimizes VM Access

• Encapsulates the Entire VM State in a Single Directory

• Simplifies Provisioning and Administration of VMs

• Provides Distributed Infrastructure Services for Multi-ESX Servers

• Facilitates Dynamic Growth

• Intelligent Cluster Volume Management

• Enables HA with Lower Management Overhead

• Simplifies Disaster Recovery

Explain P2V steps?

1. Right-click on the ESX host  and click import machine

2. Select the source machine as physical computer and click Next, provide physical computer

     hostname and administrative credentials.

3. vConverter will connect to the physical machine and Agent will be on that system.

4. Review the disk volumes

5. choose the Disk volume and ignore the page and hibernation files.

6. You can see the destination ESX host.

7. Provide name to the VM.

8. Select the datastore and NIC’s you want to connected to the new vm.

9. Install vmware tools.

10. You will be given the option to schedule the P2V conversion

11. After you click Finish, the P2V conversion (import) will begin

What is the difference between VMware and Citrix?

vmare is used for operating system virtualization and citrix is used for apllication virtualization 

What is the new features in vSphere?

In vSphere 4.0 we can add Memory and Processor along with HDD and NIC's while the machine running

What is Promiscuous Mode on vSwitch ? What happens if it sets to Accept?
If the promiscuous mode set to Accept, all the communication is visible to all the virtual machines, in other words all the packets are sent to all the ports on vSwitch 

If the promiscuous mode set to Reject, the packets are sent to inteded port, so that the intended virtual machine was able to see the communication.

What is a template ?

 We can convert a VM into Template, and it cannot be powered on once its changed to template. This is used to quick provisioning of VM's.

How does HA know to restart a VM from a dropped Host?

storage lock will be removed from the metadata

Does HA use vmotion? 

The answer is no - vm stops and restarts on ESX other host

What will VCB do for me?

What is not so great about VMHA?

1)CPU on each host must be compatible (almost exactly)

2)Virtual machines that are on the host system that goes down will have to be restarted.

What is Cloning?
With clones, you can make many copies of a virtual machine

What is Virtulization?

Virtualization is an architecture that allows you to run multiple OS simultaneously on a single computer

What is Resource pool?
A VMware ESX Resource pool is a pool of CPU and memory resources

What is dvSwitch?
dvSwitch is being centralized in vCenter and using the concept of compliance to assign a dvSwitch to a host. you will need vSphere enterprise plus to run the Nexus 1000v