Digital Pacific Company Blog

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Posts Tagged ‘Parallels’

An Introduction to VPS

Thursday, March 31st, 2011

Recently we discussed recognising when you might need to move from shared hosting to a dedicated server. What wasn’t discussed was that, for some people, moving to a dedicated server is a big commitment of time and money. While dedicated servers are an excellent option, it is a big step from a shared server to dedicated server solution.

Luckily for those people who are still unsure if a dedicated server is right for them, there is a middle ground. That middle ground is a Virtual Private Server, or VPS.

I should note that all server types play a role, from share hosting right through to dedicated servers. Each type of hosting has pros and cons that depend on your needs. Your needs will change over time, as will the type of hosting that provides the best fit your needs. The most important thing is that you choose the type of hosting that provides what you need right now.

WHAT IS A VPS?

A Virtual Private Server is just that – virtual, private and on a server. A VPS takes advantage of virtualisation to offer a dedicated hosting-like experience, albeit with a number of virtual servers hosted on the one physical piece of hardware. As the hardware is shared amongst several users, the cost of leasing the hardware is less than for a dedicated server. However, you retain some of the flexibility of a dedicated server, enabling you to get a better understanding of what a dedicated server can do for you.

HOW DOES A VPS WORK?

A VPS uses virtualisation to divide a single physical server into a number of self-contained servers. The server runs a full operating system with root access for the administrator, a guaranteed amount of RAM and has secure shell access for remote administration.

Almost all server-side virtualisation on the market today is either hardware-based or operating system-based virtualisation.

Hardware-based virtualisation uses a thin software layer, called a hypervisor, that imitates the hardware of the server, creating a copy of the system resources for each “guest” operating system running on the server. While this increases the number of different types of guest operating systems available, efficiency is reduced as the hypervisor is emulating all the hardware to maintain compatibility with different operating systems.

Operating system-based virtualisation creates a single layer of the common operating system elements and then allocates the server’s resources across each of the virtual servers, which run in “containers”. Operating system-based virtualisation is more efficient than hardware based virtualisation, as it only needs to virtualise system resources, which is then shared by all containers, rather than for each of the containers as required.

Each VPS at Digital Pacific operates in this way thanks to Parallel’s Virtuozzo server-side virtualisation software. Virtuozzo allocates the server’s resources across all of the containers and is able to dynamically allocate these resources as required. This method requires that each container runs the same type of operating system as only a single set of components is made available to all the containers.

In the case of Digital Pacific, each VPS runs a Linux-based operating system, and several different distributions of Linux are available for you to use.

MANAGED SERVERS

Administering your own server can be intimidating, as you still need to have an understanding of the basics of server administration. Digital Pacific eases the transition from shared hosting to a VPS through its managed VPS plans. The Digital Pacific managed VPS service is designed to reduce some of the workload of running a VPS for people that don’t have access to a system administrator, or don’t have the time to run the server on their own. The plans include initial server set up and ongoing maintenance (such as firewalls and operating system updates), daily backups and bundles in some additional support hours at no extra cost.

If you think you’re ready to get a taste of the flexibility of running your own server, be sure to check out Digital Pacific’s managed and unmanaged VPS plans today.

An Introduction to VPS

An Introduction to VPS An Introduction to VPS An Introduction to VPS An Introduction to VPS An Introduction to VPS An Introduction to VPS An Introduction to VPS An Introduction to VPS An Introduction to VPS

Virtual machines: the essential tool for all web developers

Thursday, December 9th, 2010

Creating web products that look the same for everyone on the internet is not easy. With different browser vendors, operating systems and even different versions of browsers competing for market share, designers and developers need to take account of many things when creating new products. An effective way to address the problem is through “virtualisation”.

What is virtualisation?

Virtualisation involves running a special program that simulates a real computer in software, called a virtual machine . The virtual machine acts like a container inside the operating system, isolating the program from the main, or host, operating system. For example, a virtual machine running on the host Mac OS X operating system enables you to run Windows software on a Mac computer by convincing the Windows program it is actually running on a Windows PC instead of the Mac.

The benefits of virtual machines

Web designers and developers create products that need to look similar and work as intended across different browsers and different operating systems. Cross-compatibility becomes expensive if you are expected to own both a Mac and a PC (or even a third computer if you want to test on niche operating systems like Linux ).

Maintaining compatibility with different versions of Internet Explorer introduces its own problems. It is only possible to have one version of Internet Explorer installed at a time. However, there are still many users of older versions of Internet Explorer. Internet Explorer 6 still has around 15% market share , and it is light years removed in functionality and support for web standards compared to version 8 or the upcoming version 9.

Mac users are able to take full advantage of the benefits of virtual machines. By using software such as Parallels, they are able to virtualise other operating systems, including Windows, as well as running Mac OS X.

Windows users are not so lucky. Licensing requirements prohibit running Mac OS X desktop on anything other than genuine Apple hardware. This means that technically it is against Apple’s terms of service to virtualise OS X. However, virtual machines on Windows do allow designers and developers to get around a different problem – testing against various versions of Internet Explorer.

Which virtualisation software should I use?

There are a range of free and commercial virtualisation programs available, each with its own benefits.

Parallels

Parallels has offered virtualisation products for a long time and has several products for both enterprise and consumer-level customers across the Mac, Windows and Linux platforms,. Parallels is well known due to its successful Parallels Desktop for Mac. For Mac users, Parallels is arguably the best choice for virtualisation, as even the previous version performed better than its nearer competition .

Parallels also offers Virtuozzo which creates isolated virtual environments (VE) or containers on a single physical server and OS instance. Digital Pacific offers Virtuozzo as part of its VPS hosting plans.

VMware

Like Parallels, VMware is a company of long standing. It also has products on Mac, Windows and Linux. VMware has released the free VMware Player. VMware Player is Windows only and has fewer features than the commercial product.

VirtualBox

Released by Sun Microsystems, VirtualBox is open source and runs on Windows, Linux and Mac. Free for personal use, it can host quite a few different operating systems including Linux and most versions of Windows (including Windows 7). While it doesn’t boast all of the features of its commercial competitors, it is ideal for quick testing on your desktop during the development and bug testing stage.

Windows VirtualPC

Windows VirtualPC is Microsoft’s virtualisation product and is available from Microsoft as a free download or as part of the higher end versions of Windows 7. Although promoted as a way of running old Windows software inside Windows 7, it can also be used to host other operating systems. In addition, Microsoft offers special editions of Windows running different versions of Internet Explorer which can only run inside VirtualPC. These versions have been released expressly for testing different versions of Internet Explorer.

Ultimately, it doesn’t matter which virtualisation solution you choose. The important thing is that you choose one and get started. With a virtual machine as part of your design toolkit, you can now have confidence that you can offer your clients and customers a truly cross-platform product.

Virtual machines: the essential tool for all web developers

Virtual machines: the essential tool for all web developers Virtual machines: the essential tool for all web developers Virtual machines: the essential tool for all web developers Virtual machines: the essential tool for all web developers Virtual machines: the essential tool for all web developers Virtual machines: the essential tool for all web developers Virtual machines: the essential tool for all web developers Virtual machines: the essential tool for all web developers Virtual machines: the essential tool for all web developers

Every bug in the world can be solved with just 15 new lines!

Tuesday, May 26th, 2009

Customers of Digital Pacific will be happy to know that in a few months time, we will be moving to a new; more feature complete billing system that will provide many benefits to users. With our new billing system, Parallels Business Automation, users will be able to see all their invoices (past, present and future) and will be able to literally click one button and switch between all of their hosting control panels.

This move, however, has not been without quite a number of funny mishaps while moving from our current billing system (ModernBill) to Parallels Business Automation (“PBA”). The following text is going to go into quite a bit of technical information, so if you don’t know what XML is, well, you might just want to close this window go to Wikipedia’s article on XML and look it up!

Observe this image very closely:

Every bug in the world can be solved with just 15 new lines!

So what I have done, is I have made a set of files with 100 customers each. Every separate file gets imported by running the command on the PBA server ‘hspc-import.pl’. Here, I am running the 59th file (the files start at 00). hspc-import.pl is complaining that the email for person “Becky A. Douglas” is not defined, however, when I go to edit the file, the email is infact correct, and it is definitely defined. Just like it is for the clients before her.

This issue has had me baffled for weeks trying to solve this issue. Sometimes it works, sometimes it does not. Sometimes changing the name in the XML file will just magically solve the issue, as if it was not there to begin with.

So what I do, is I get on Skype and call our Sales Engineer at Parallels, and tell him what the issue is. He points out a few issues with the XML file (which is fair enough, but why did all the clients before these “just” import without any issues?).

I take into account the issues that he pointed out, and go and create a new set of import documents to get our clients into our new billing system. I run all the commands again to start the process rolling, and now the issue is coming up again!

But now something very, very bad is going on! The import is actually failing faster then it was before the fixes that were suggested by our Sales Engineer. So I back track and change a few lines in the XML file. Instead of the top of the file saying this:

<?xml version="1.0" encoding="UTF-8"?>
<data>
<account>
<type>CUSTOMER</type>
<status>active</status>
<is_corporate>0</is_corporate>
<name>Bob Smith</name>

It now says this:

<?xml version="1.0" encoding="UTF-8"?>
<data>

.
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.
.
.
.
.
.
.
.
.
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.


<account>
<type>CUSTOMER</type>
<status>active</status>
<is_corporate>0</is_corporate>
<name>Bob Smith</name>

After adding exactly 15 new lines after the <data> child in the failing XML file in the import batch, you wouldn’t believe it. The import actually succeeded.

So now my new motto is, “Every bug in the world can be solved with just fifteen newlines!“.

Every bug in the world can be solved with just 15 new lines! Every bug in the world can be solved with just 15 new lines! Every bug in the world can be solved with just 15 new lines! Every bug in the world can be solved with just 15 new lines! Every bug in the world can be solved with just 15 new lines! Every bug in the world can be solved with just 15 new lines! Every bug in the world can be solved with just 15 new lines! Every bug in the world can be solved with just 15 new lines! Every bug in the world can be solved with just 15 new lines!