7 Domain Name Generators


1.) NameBoy - This is a helpful generator which allows you to enter keywords and ideas and comes up with a unique and intelligent combination for your domain name. It also has a couple checkboxes such as allowing hyphens or rhyming. When it gives you your results it shows the possible extensions that the domain is available in.

2.) Domain Name Generator - This is a very intelligent tool which comes up with great name creations based on the criteria your provide. It is very detailed and offers options for languages, prefixes and suffixes, character length, and more. Highly recommended.

3.) Whoix? - The Whoix? Domain Name Wizard is great if you already have an idea of what you’d like to call your site, but you need plenty more suggestions and variations. It’s simple: all you do is enter in a domain name and extension you would like, and Whoix? offers you other ideas. Quick, easy, but immensely valuable.

4.) NameDroppers - With this, you can quickly search for, create, and register your domains if you’d like. There are a lot of options you can select through, including keyword order, character length, excluding numbers and certain keys, what extensions you’d like and which ones you don’t, and more. There’s even the ability to choose whether you’d like to view only nonexistent domains, already registered ones, or both.

5.) Domain Name Generator - This one is extremely simple to use. You only have to fill in one box, which is your relevant word or phrase, and it offers you possible domain names and alternatives. On top of that, this site also has some other great tools, so check them out as well!

6.) SnapItNow - This neat domain generator has nine options, including ones for keywords, categories, hyphens, flip-flopping your keywords, hiding taken domains, choosing certain extensions, etc. There’s not much involved so it makes your job a whole lot easier.

7.) Name Generator - And last but not least, there’s the Web 2.0 Name Generator. This one is different from all the others but it still has something to offer. Instead of coming up with domain alternatives, this one randomly gives you unique names that you can use to title your own site or blog. Upon clicking the “Generate Name!” button it offers you a new choice, so you can go through them until you find one you love - and then when you do, you can click another button to check its availability. And so you don’t lose any names, it neatly lists all your previously viewed ones in the sidebar.

Try it out!

Friday, September 21, 2012
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New in Vsphere 5.0 Storage : Part 2


In vSphere 5 VMware includes Storage Distributed Resource Scheduler. Storage DRS perform automatic load balancing if a disk becomes overloaded and automatically load balance IO activity. Storage DRS decrease operational efforts associated with the provisioning of VM and monitoring of the storage environment.

In vSphere 5.0 VMware comes up with a new object in vCenter called DataStore Cluster. DataStore Cluster forms the baseline of Storage DRS. Similar to cluster of host, a DataStore Cluster aggregate storage resources. Storage DRS gets enabled by own once we create Data Store Cluster. Once we have Storage DRS enabled, the datastore cluster becomes a load – balancing domain. We can have VMFS – 3 & VMFS 5 member of a DataStore Cluster but mixing of NFS & VMFS is not supported.

Storage DRS provides initial placement and ongoing balancing recommendations based on space & I/O Capacity.  During VM provisioning, a data store cluster can be selected as target destination for VM or Virtual Disk. Ongoing balancing recommendations are made once data stores in a cluster exceeds configured space utilization or I/O latency thresholds.
Similar to HOSTS based DRS, Affinity rules can be configured in Storage DRS. Storage DRS offers three types of affinity rules

VMDK Anti – Affinity : Virtual Disks of a VM with multiple virtual disks are placed on different data stores.

VMDK Affinity : Virtual disks are kept together on the same data store

VM Anti – Affinity : Two specified virtual machines, including associated disks are placed on different datastores.

Storage DRS also offers Datastore Maintenance Mode, which automatically evacuates all VM & Virtual Disks from selecting datastores.
Tuesday, September 11, 2012

New in Vsphere 5.0 Storage : Part 1


                    vSphere 5.0 introduces a new version of vSphere VMFS i.e. VMFS -5 to provide great scalability & performance with much simpler management.

The first step is to reduce the storage objects to manage i.e. fewer and much larger datastores. Fewer and much larger datastores is  being achieved by implementing UNIFIED BLOCK SIZE, which is 1 MB this removes the limitation of maximum size for a datastore limited like earlier versions.

Enhancements in VMFS-5

Large files can be created on VMFS – 5 using 1 MB file blocks

In VMFS-5 extent of size 60 TB can be added if Extent volume is with UNIFIED Block Size of 1 MB,  It was 2 TB earlier.

Smaller sub-block of 8 KB ( was 64KB earlier)is introduced in VMFS – 5. This reduces the disk space utilization for small files i.e. more than 1 KB but less than 8 KB.

In VMFS – 5 files less than or equal to 1 KB are stored in descriptor location in metadata instead of file blocks.

VMFS – 5 supports greater than 100000 filese it was 30000 in VMFS – 3

ATS ( Atomic Test & Set ) is now used  for file locking in VMFS – 5

Datastores can be upgraded from VMFS – 3 to VMFS – 5 without any downtime. Upgraded volumes to VMFS – 5 will retain their orignial block size as modifying block size requires reformat of the volume.

Standard Virtual Switch Architecture

Standard Virtual Switch Architecture

             Now let’s take a few minutes to discuss the components of the standard switch architecture which is driven from the host level

To the outside world, the vNIC has its own MAC address and one or more IP addresses and responds to the standard Ethernet protocol exactly as a physical NIC would. In fact, an outside agent can determine it is communicating with a virtual machine only if it checks the six byte vendor identifier in the MAC address.

A standard switch, or standard virtual Switch, works like a layer-2 physical switch. It maintains a MAC: port forwarding table and performs three important functions:
  1. It looks up each frame’s destination MAC when it arrives. 
  2. It forwards a frame to one or more ports for transmission.
  3. And, it avoids unnecessary deliveries. In other words, it is not a hub.
 Each ESX/ESXi host has its own standard virtual switches. You can create up to 127 virtual switches on each ESX/ESXi host. 

On one side of the virtual switch are port groups that connect to virtual machines. On the other side are uplink connections to physical Ethernet adapters on the server where the virtual switch resides.
Virtual machines connect to the outside world through the physical Ethernet adapters that are connected to the virtual switch uplinks. ESX supports high performance networking for running the most demanding workloads in virtual machines.

A standard switch can connect its uplinks to more than one physical Ethernet adapter to enable NIC teaming. With NIC teaming, two or more physical adapters can be used for load balancing or to provide passive failover in the event of a physical adapter hardware failure or a network outage.
The virtual ports on a virtual switch provide logical connection points among virtual devices and between virtual and physical devices. You can think of the ports as virtual RJ-45 connectors. Each virtual switch can have up to 1,016 virtual ports, with a limit of 4,096 ports on all virtual switches on a host. However, this system-wide limit includes eight reserved ports per standard vSwitch, so you can use only 4088 ports.

A virtual Ethernet adapter updates the virtual switch port with MAC filtering information when it is initialized and whenever it changes. A virtual port may ignore any requests from the virtual Ethernet adapter that would violate the Layer 2 security policy in effect for the port. For example, if MAC spoofing is blocked, the port drops any packets that violate this rule.

 Port group is a unique concept in the virtual environment. A port group is a mechanism for setting policies that govern the network connected to it. Instead of connecting to a particular port on the standard vSwitch, a virtual machine connects its vNIC to a port group. All virtual machines that connect to the same port group belong to the same network inside the virtual environment even if they are on different physical servers. Port groups can be configured to enforce a number of policies that provide enhanced network security, network segmentation, better performance, higher availability, and traffic management.

VMware vNetwork Distributed Switch Architecture

VMware vNetwork Distributed Switch Architecture

                  Now let’s look at a diagram that shows the distributed switch architecture which is driven from the datacenter level and is the recommended architecture to use when you are setting up your vNetwork.

First off we have distributed switches. A distributed switch acts as a single virtual switch across all associated hosts. This allows virtual machines to maintain consistent network configuration as they migrate across hosts. Like a standard switch, a distributed switch is a network hub for virtual machines. A distributed switch can route traffic internally between virtual machines or link to an external network.

 Distributed switches are managed entities configured inside of vCenter Server.

 Distributed switches exist across two or more clustered ESX or ESXi hosts. vCenter Server owns the configuration of distributed switches, and the configuration is consistent across all hosts. The uplink ports on the distributed switch link to uplink ports on hidden vSwitches. The hidden vSwitch uplink ports connect to physical NICs, which then connect to the physical switch ports.

Be careful not to confuse a distributed switch with a single switch spanning across several hosts. Two virtual machines on different hosts can communicate with each other only if both virtual machines have uplinks in the same broadcast domain. Consier a distributed switch as a template for the network configuration on each ESX or ESXi host.

 Each distributed switch includes distributed ports. A distributed port represents a port to which you can connect any networking entity, such as a virtual machine, the service console, and so on. vCenter Server stores the state of distributed ports in the vCenter Server database, so networking statistics and policies migrate with virtual machines when moved from host to host. This network vMotion feature is key to implementing state-dependent features such as inline IDS/IPS firewalls, and third-party virtual switches.

Distributed port groups perform the same functions as port groups in standard vSwitches:
  1. They provide a way to logically group distributed ports to simplify configuration,
  2. They inherit and can override all distributed switch properties,
And they do not constitute the means to segregate traffic within the distributed switch (unless you use Private VLANs).

How VMware vNetwork Distributed Switch work if vCenter fail

Within a distributed switch, the control and IO planes are separate:

                The control plane resides in vCenter Server. The control plane is responsible for configuring distributed switches, distributed port groups, distributed ports, uplinks, NIC teaming and so forth.

The control plane also coordinates the migration of the ports and is responsible for the switch configuration. For example, in the case of a conflict in the assignment of a distributed port (say because a virtual machine and its template are powered on), the control plane is responsible for deciding what to do.

The IO Plane is implemented as a hidden vSwitch inside the VMkernel of each ESX or ESXi host. The IO plane manages the actual IO hardware on the host and is responsible for forwarding packets.


This diagram shows a more detailed look at the components of the IO plane of a distributed switch.

On each host, an IO plane agent runs as a VMkernel process and is responsible for communication between the control and IO planes.

IO filters are attached to the IO chains connecting the vNICs to the distributed ports and the distributed ports to the uplinks. vNetwork Appliance APIs make it possible to define custom filters and apply them to the IO chains. The APIs also provide the means to preserve filtering information for the virtual machine connected to each port, even after vMotion.
Inside the IO plane, the forwarding engine decides how to forward packets to other distributed ports, either toward other virtual machines on the same distributed switch, or to an uplink, requiring it to make NIC teaming decisions. Forwarding functions can also be customized using the vNetwork Appliance APIs.

So in case vCenter server goes down still Virtual machine can contact outer network with the help of hidden vSwitch

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