We transfer the entire office to the "cloud": not a byte on local machines

The principle is very simple: you need to leave each user to use the simplest machine with a browser, and keep all applications and all data in the data center. There, in the data center, you can create for each user a virtual desktop, where you can go by analogue of RDP.

For all this to work properly, you need a solution that will ensure the availability of such desktops in the cloud, application delivery, data management, and information transport from I / O devices to the end user. This is Citrix XenApp .

To make it all work almost out of the box and one and a half times cheaper, we made a very interesting SaaS solution in our cloud . But first, let's go through the main points that facilitate the work of the IT department and save money.
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Convenience management

When all the working machines are actually located in the data center, they are very easy to manage. We are talking about creating a working machine with assigned rights and policies, which runs in the cloud as a separate virtual server for specific users. If it is necessary, for example, to add one application to all engineers of a company, this is done not by changing objects, but by one modification of the class. In fact - a couple of clicks in the settings of the virtual desktop template. Updates do not take more than 20 minutes and concern all necessary workstations at once.

Convenience support

The user has a physically installed machine that functions as a terminal: it can be anything on which the browser starts up - even the Raspberri Pi, even the “Gorynych serpent” with three monitors on one sistemnik, although the usual office cheap monoblock (most often).

The operating system is not important: the thin client runs anywhere.

User terminal performance is not important: even if it works with high-loaded applications, this load falls on the data center servers.

This park of computers is very easy to maintain. Moreover, the beauty is that the user data is also stored in the data center (and not on its access terminal), that is, for any failure, it is enough to bring a new system organizer or put the user at the next table to completely solve the problem. Once again: no failure of iron will lead to data loss, and no failure of iron will require more than 15 minutes to correct.

Easy access

You can connect to a remote desktop from anything: from a tablet, from a phone, from any computer from which the system administrator allowed you to log in to the data center - including from a home one, if necessary. This means the simple fact that you can work anywhere and in any way. Forgot your laptop at home? It's okay, you can always reach out to your usual working environment from anywhere.

Architecture

XenApp is a solution included in the Citrix Delivery Center (XenDesktop, XenApp, XenServer, NetScaler, and Citrix Receiver), designed to deliver any Windows applications. This solution provides application virtualization, centralization and data management of applications from the data center, plus gives access to the application using the Software as a Service (SaaS) model upon request to any user device, regardless of its location. For the delivery of the application, the proprietary ICA protocol was previously used; now the latest versions of XenApp use the multi-stream High-Definition User Experience protocol (thanks to which traffic is minimal).

In order for the application to be delivered to the end client, either Citrix Receiver or Citrix SmartAccess is required. The first is a software solution for providing remote desktops and enterprise applications installed on the provider's site or, in our case, in the “cloud” of the SaaS model. However, his work does not require control from the IT services. There are implementations of Citrix Receiver for Windows, Windows Mobile, iPhone, iPad, Android devices, Mac OS X and Linux. The second is a web-interface without downloading client software.



The basic principles of work are as follows:

1. The user connects to the load balancer or directly directly from one of the Citrix nodes in the data center.
2. A desktop is created on the terminal server where the user is connected.
3. User login to this virtual workstation.
4. From the user to the Citrix node and back, only monitor data (down) and keystroke data plus mouse movements (up) go. That is, in fact, it is an analogue of RDP.
5. From the Citrix node, there are requests inside the data center to the database, with which applications work.

What does it mean?

• The traffic between the user and the platform is minimal.
• The application and its database does not pull up to the local machine, but runs on data center servers. While the solutions of the past generation imply that if the user “knocks” from Omsk, and the data center in Moscow, then he will have an unpleasant surprise in the form of slow work and a lot of traffic.
• The user, in fact, connects his screen, keyboard and mouse to a virtual machine located right in the heart of the data center.
• At the same time, data transport to the user is well protected - therefore, one of the few ways to compromise security is simply to photograph the user's terminal screen.
• All data is in the data center and stored between sessions in the same place.
• Once the data in the data center - even with force majeure in the office data remains intact, safe and inaccessible to third parties.

Our practice shows that the situation is quite real when 600 client workstations are managed by one sysadmin, plus a pair of enikeyschikov who dealt with issues with hardware. As workstations, only thin clients are used instead of PCs - just boxes to which a keyboard, mouse and monitor are connected. They have nothing to really break: there is no hard disk, there is no cooler, in principle there are no mechanical things.

Why do you need a "cloud"?

It is clear that so far all of the above can be implemented without a “cloud” approach, simply by purchasing a dozen servers. However, it is clear that more than half of the time they will be idling: after all, their use stops at the weekend, at night, drops at lunchtime, and so on.

The “cloud” allows you to scale horizontally as you like and pay only after use (at the moment: servers, but not licenses). This is a direct cost savings.

The “cloud” makes it possible not to think about scaling up when new jobs are launched (even though at once in whole departments) and increasing the load on existing ones.

"Cloud" allows you to balance the load between the servers.

In practice, there are three options: in the classical scheme with the purchase of servers, the machines simply work, which is wildly uneconomical. In another approach, you can turn off the machine manually, it also provides some savings, but still inconvenient. In the approach implemented by us in the “cloud” of CROC, it is possible to configure automatic on-off servers according to load or schedule. This solution works with the use of a standard cloud API and built-in mechanisms for managing a Citrix farm.

How does this work in conjunction with the KROK cloud?

You want to have terminal servers in the cloud. Suppose they will connect your company's customers. You can build a graph of the load depending on time. For example, at night, there are no remote desktop users at all. At the time of the peak, at 14 o'clock, there are 600 users. It turns out that the peak load (even if it is 600 users) requires 20 servers, 300 users - 10, and at some point one server is enough. Terminal servers are turned on and off depending on the number of users.

The result - savings due to the fact that you do not have to pay for the downtime of the server infrastructure. At the same time, the cost of software development for linking Citrix to the “cloud” bounces off, as a rule, after 6 months due to this saving. The software is configured individually for each customer. For example, you can configure it so that the additional server starts when there is only five users left on the previous one. You can make the servers start on a schedule, or you can configure automatic removal of the user's desktop if it is inactive for more than two hours. Plus any other wishes of the customer.

As a result, up to 80% of the funds previously required for server operation are saved. Plus - IT-department is unloaded from the routine and leads to the fact that the chaos at workstations ended once and for all.

I think that already in 5-10 years there will be very few offices where applications will work on local machines.