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Servers in the USA, Data Center COPT DC-6-EvoSwitch / LeaseWeb (Manassas)

For a long time, I was skeptical about the idea of ​​hosting servers anywhere else except in the Netherlands. So why why? In the Netherlands, excellent connectivity is probably the best in the world, loyal legislation, and the most pleasant prices for the rental of dedicated servers in one of the most reliable data centers, which is perhaps the most important. Nevertheless, some clients persistently demanded a second location, preferably in another country, owners of rare paranoia also met, and some of the audience was directed to the American continent and there was little direct connectivity to the United States, there were unique people who simply thought that the United States was better , why is it better - they themselves did not know ...



In July, finally “dying” from boredom and summer coolness, we still thought, not whether to expand our presence on the Internet, adding a new reliable location, especially Jay Devin, one of the main managers in the US, has been campaigning for more than half a year visit COPT DC-6-EvoSwitch / LeaseWeb (Manassas), without stopping vain attempts in the style of "well, order at least something, we also need customers."
')
Nevertheless, before entrusting our customers to Americans, we wanted to make sure that everything is really high there, since the data center is very different from the Dutch (the owner is not LeaseWeb), and the number of LeaseWeb servers located in Manassas is much lower than in the Netherlands Haarlem - for February of this year, about 3000, which LeaseWeb moved entirely from one server to another:



Yes, well done guys, what to say ... Servers grow from a smaller server to a larger one, which is probably acceptable at the initial stage. But even though this was all professionally accomplished (immediately after the end of the transfer, Jay sent a link to the video, apparently they were very proud of the fact that all clients remained intact :)), I didn’t want to repeat this move and this video even scared me a little more action, although Jay guaranteed that this will not happen again and now the expansion will take place on a different scheme.

There was a time in July and a reason - they decided to check, and why not. Although July is certainly not the best time to visit the United States, it’s hot, but since our Dutch colleagues were there at that time, other issues could be solved at the same time and you could have a good time. After seeing the forecast, where they promised a joyful +33 for the day after tomorrow, they bought tickets to Washington. Never believe gismeteo predictions if they concern the USA! If in other regions they are more or less true, then in the USA they probably have problems with accuracy ...



Upon arrival in Washington with a delay of one hour (which is consistently observed on AirFrance flights, I’ll do anti-advertising, even on Habré, they got it, the French :)), this time because of searching for passenger’s baggage, who wanted to leave a huge two-story plane the moment, the joyful voice of the flight attendant told us that it was sunny outside, the temperature was 114 degrees Fahrenheit or +45 Celsius. I thought it was wrong ... But after leaving the air-conditioned airport, they realized that it was not, +45 in the shade, even more in the sun ... The benefit of a taxi was not far away. We were told that in the USA there is an abnormal heat for several days. It was just hell, the radio broadcast about the victims of this abnormal weather and the increase in the number of "cooling stations", where you could recover. It became interesting how the data center functions in such temperatures :)

I immediately remembered a case in Moscow, when during an abnormal summer heat at temperatures much lower, the servers in several data centers shut down, since the air conditioning did not cope, and then +45 in the shade ... Whoever has ever been in such extreme temperatures, you know - it's only interesting a minute then you think how to escape from it.



Perhaps it is good that the first in the program was an inspection of the air-conditioned data center. The next day, early in the morning, having left the center of Washington (and we stayed in a hotel on Capitol Hill, I recommend the Capitol Hill Hotel of the same name if you want to visit the capital, though the best option), in spite of the small trudge in the city in 50 minutes we were in Manassas. Another 10 minutes was spent searching for the LeaseWeb office building, which is quite far from the data center, lost among other office buildings, and has a new number, which for some reason is not in the GPS database.

Nevertheless, there were. Jay and Yulia, who met us and envied our shorts and light T-shirts (Jay's first words are “I would wear shorts too, if I knew you were wearing shorts” :), who were themselves in business style in such hot weather, invited me to go to their office. In the office, unlike the street, there was a terrible cold, Americans have an unhealthy perception of conditioning, apparently they do not know that sudden drops in more than 10 degrees are extremely harmful for an ordinary person. Immediately, the difference in temperatures of more than 25 degrees (on the street more than +45 in the shade, indoors +20, and maybe less), the shock to the body is huge!



Now to the main point - about the data center. LeaseWeb has significantly fewer employees in the United States than in the Netherlands, less than two dozen people, because the data center operator is not EvoSwitch / LeaseWeb, but COPT, which manages the Data Center, ensures its work and security, providing customers with the infrastructure for housing cabinets and servers.

Corporate Office Properties Trust (COPT)


• A public mortgage investment trust with a total capital of over $ 4 billion.
• Owns, developed and / or performs the management of Data Centers with a total usable area of ​​over 200,000 square meters. meters, including COPT DC-6 in Manassas, Va.
• Awarded numerous awards.
• Has experience in working with specialized US government data centers.
• Has experience in working with sensitive compartment information objects (SCIF) and in the design of communication rooms.

COPT DC-6 (formerly Power Loft)



• 3,600 square meters of directly usable space for hosting IT infrastructure.
• 5 MW maximum power.
• Ability to expand to 9 MW and 2,600 square meters for 6 months.
• Container compartment modules are available for placement.

Low cost of operation:

• Using the environment for cooling saves 10% of energy or $ 144,000 / year.
• The power efficiency is 1.3 (versus the industry average of 1.8), which gives savings of $ 240,000 / year.
• Own water resources provide savings of $ 26,400 / year.
• Total annual savings in COPT DC-6 are $ 4,10400 / year.



Tax savings:

• Equipment tax is 70% less in COPT DC-6 (Prince William District) than in the center of Ashburn (Laudun District) or in Fairfax County.
• Savings of $ 125,000 per million invested in equipment for 10 years.

Security features:

• 22 miles from Ashburn and, accordingly, from the concentration of risks for the Data Center.
• ATFD (ANTI TERRORISM / FORCE PROTECTION) patrols the site more than 50 meters from the building.
• Engineering systems are separated from IT objects.
• Space to accommodate sensitive data bays allocated and ready to use.
• Meets requirements of the US Security Department and Central Intelligence Directives.
• Complies with the requirements of the FISMA (Federal Information Security Management Act - Federal Law "On Ensuring Information Security").



Solutions for modular data centers:

• Ready territory plan.
• Support for double-width containers.
• Use of available cooling water resources, UPS and generators.

Advantages of Manassas


Advantages of the location of the Data Center in Manassas:

• 22 miles from Ashburn and its regional risk concentration for Data Centers.
• Location outside the main routes of Dulles International Airport.
• Tax on property of individuals in Prince-William County is 70% lower than in Loudoun County.
• The cost of total operation is lower than at Ashburn Data Centers.
• Compliance with all location requirements for Data Centers.
• Use of a power grid separate from Ashburn City.



Connectivity and delays:

• The Innovation Park in Manassas, Prince William County, is extremely rich in fiber-optic networks.
• Multiple retail and wholesale backbone providers provide direct and secure connection to traffic exchange points in Ashburn and to the main state traffic exchange points of Virginia, Maryland and Washington.
• No difference in latency between Manassas and Ashburn.
• The delay to the regional NAP (network access point) is 5 times less than in the service agreement of the New York Stock Exchange.
• Selected dark fiber connections to government sites are available.
• Certification capabilities include FISMA (Federal Information Security Management Act - Federal Law "On Ensuring Information Security"), ITIL (IT Infrastructure Library - Information Technology Infrastructure Library) and SAS 70 / SAE 18 (Audit Standards Act No. 70 / Community automotive engineers, act 18).



Reliable fiber and communications infrastructure


COPT DC-6 provides reliable fiber optic communications from companies such as AboveNet, Level 3 Communications, FiberLight, Verizon, Comcast and NOVEC. Many providers are located nearby, due to which getting their services is extremely simplified. The state safe connection is located in close proximity, direct connection is possible according to the approved requirements.

The location of the COPT DC-6 allows you to connect directly with several providers to the main network access point located in Ashburn, Virginia.

Fiber-optic providers have access to the Data Center through two different underground inputs and fiber-optic connections go directly to two different switching rooms, interconnection nodes (MMR). The connection is distributed over two additional MMRs, providing a total of four MMRs. Due to this, one MMR covers 2300 square meters of raised floor, providing multiple paths and redundant connections to each Data Center area.

COPT DC-6: Square and Rack Plan




WESTERN WING \ Section 201-208

Available now:
Section 203-205
• 1560 sq. M. m
• 2 MW maximum load.
• The possibility of increasing the load to 4.5 MW.

Available in the future:
Section 207:
• 440 sq. M. m
• 1 MW maximum load.



EAST WING \ Section 209-216

Available now:
Section 209-211
• 1560 sq. M. m
• 2 MW maximum load.
• 15 power distributors.

Available in the future:
Section 212-216:
• 2600 square meters. m
• 8 MW maximum load.

Features of placement:

• 254 cabinets can be placed in a compartment area of ​​520 square meters. meters
• The space freed from climate control systems (due to the use of the environment) is used by the tenant to install 50% more cabinets.
• Flexible power - from 1 kW to 3.2 kW per square meter. meter of usable area.



Benefits:

• The reliability level of Data Center 3+ (Tier III).
• Power efficiency ratio is 1.3.
• Flexible design - the ability to use static and rotor UPS.
• The gold standard for energy efficiency and environmental design (LEED-NC Gold), the highest level of energy efficiency.
• Isolation of engineering systems.
• Preventing the generation of excess energy - not a single point of failure.
• The most advanced network management center (NOC) and integrated management reporting system.
• Water and air economizers reduce energy consumption and operating costs.

Innovative design


Separation of engineering systems from IT space:

• Simple division into sectors.
• Minimizing disruption.
• Preservation of the possibility of growth of useful space for cabinets
• Clear security separation.

Ventilation unit with recirculation with cooling (AHU) instead of climate control units (CRAC):

• 160 ton AHU instead of 20 ton CRAC.
• Variable Frequency Drive (VFD).
• Unique air recirculation system.
• Support up to 3.2 kW per square meter. meter (@ n + 1min.)



Chilled water circulation:

• Simultaneous maintenance.
• Lack of water over the raised floor.
• Taps for internal cabinet cooling.

Federal Compliance:

• COPT DC-6 meets the most stringent Federal security standards, which include: at least 150 feet from the facility to traffic checkpoints, traffic barriers, K-12 fencing, secure entrances, turnstiles, biometric access control and several video surveillance zones.
• The facility complies with SAS 70 II and SSAE 16 standards and can support FISMA, a high level of network certification.
• COPT DC-6 is one of 10 properties selected to host the GSA Cloud.

Working efficiency:

• COPT DC-6 uses 70% less energy than traditional construction objects in Northern Virginia.



High density scalability:

• COPT DC-6 design allows users to increase maximum power consumption and cooling for higher density cabinets with minimal damage or loss of raised floor space using air or single block cooling.
• The building was designed to remove heat up to 3.2 kW per square meter using air, which allows placing equipment with high density when using water cooling in cabinets.
• Installation of cooling water saves water resources, and the building - to save air.

Reliability:


• COPT DC-6 is designed to provide a level of reliability of N + 1, which is classified as Tier III + according to the criteria of the Uptime Institute.
• It is possible to increase the number of uninterruptible power supplies by 2N, which will increase the level of reliability to Tier IV.
• COPT DC-6 is under the authority of COPT employees, and COPT is fully responsible for security, providing a guaranteed service level under the agreement (SLA), monitors all systems, from the closed perimeter video surveillance scheme to a separate device. All these devices are controlled 24/7 from a separate (outside the facility) Network Control Center.



Green design:

• COPT DC-6 is a LEED NC Gold certificate holder.
• Engineering systems significantly save water and air.
• The roof surface consists of a white stone reflecting sunlight.
• An automated lighting system for premises and territory is used.

Location:

Innovation Park:

COPT DC-6 is part of Prince-William County Innovation Park, 4 sq. M. km ideally planned business park, positioned as a “technology incubator”. Managed by the economic development department of Prince William County Administration.

Distance from Washington:

• The Innovation Park is located 30 miles from Washington, i.e., 45 minutes away from the center of Washington.
• You can get there by road 234 or I-95 to the south or I-66 to the north. Manassas railway station is 1.5 miles to the south, and Dulles Washington Airport is 15 miles to the north.



Resources:

Water

The water comes from two wells that can keep the systems running even during the hottest days of summer in Virginia. In this regard, the cost of monthly maintenance does not include a water bill.

Electricity

NOVEC provides more than 50 MW of power for dedicated 34.5 kV communications. In addition to this, in order to protect COPT DC-6 from reducing the quality of the supply of electricity by increasing the load on the network, NOVEC makes it possible to increase the power by another 50 MW.



Power supply from multiple transmission sources

• Substations from Laudun / Gainesville / Vulcan.
• New radial 34.5 kV circuit with 50 MW power.
• Dedicated power channels = improved power quality.

Additional backup 34.5 kV circuitry from substations in Ox and Canon Branch (Ox / Cannon Branch).

Main data center characteristics


Raised floor:

• 9,290 square meters of raised floor
• 16 compartments, each of which is provided with 1,875 MW
• 1220 kg maximum load per square meter
• The possibility of expanding the power consumption from 1.6 kW to 3.2 kW per square meter without downtime or loss of the raised floor area.

Power System:

• 5 x 2.25 MW of diesel power plants (critical power 1.25 MW).
• Configuration in the 6 MW unit - 4 main, 1 reserve.
• Rotary or static UPS.
• Lack of electricity parallelism.
• No emergency power off system.
• 2 MW diesel generators provide N +2 power for engineering systems.
• Grid topology allows you to use connections with alternating (AC) and direct (DC) current.
• Modular design provides the ability to increase power with minimal disruption and as soon as possible.



Fuel storage:

• Up to 2.275 million liters of ultra low sulfur diesel fuel.
• Fuel cleaning system, piping system for excess fuel.

Climate control:

• 11,400 tons of refrigeration
• 60 x 60,000 CFM for air handling
• High water cooling efficiency
• Saving air and water from external sources
• 20 minute chilled water reserve
• Water supply wells in the territory
• Simultaneous operation of chilled water cycles
• N +2 excess resources
• No water above the raised floor

Firefighting:

• Using a dry pipe sprinkler system.
• The iVESDA fire detection system is installed in accordance with HPCS requirements.

CONTROL SYSTEMS

Four Siemens modules: EPMS, BMS, Security and Life / Fire / Safety

Currently, our partner LeaseWeb US in COPT DC-6 has the following capacities:

- more than 7000 servers;
- more than 40 free cabinets for equipment placement, not including already available servers with instant activation;
- a dedicated room for equipment;
- the possibility of increasing the capacity of communication channels up to 3.5 Tbit / s;
- the possibility of reserving neighboring isolated rooms-modules for expansion.



And best of all - despite the fact that the location service in the US is more expensive, +45 is not the Netherlands :), we are ready to offer similar prices for servers with a channel from 100 Mbit / s to 10 Gbit / s.

http://ua-hosting.com.ua/us-servers.html - servers with fast activation are always available, for example:

US - Intel Dual-Core G6950 / 4GB DDR3 / 2x250GB SATA2 / 100Mbps Unmetered - $ 65 / month
US - Intel Xeon E3-1230 / 8GB DDR3 / 2x500GB SATA2 / 100Mbps Unmetered - $ 89 / month

The remaining configurations are provided for as short a time as possible after the order, as well as the configurations to which the upgrade is ordered.



We now show the actual connectivity.

Connectivity to Ukraine is at 130 ms:

[root @ us3 ~] # tracepath dc.ukrtelecom.ua
1: us3.ua-hosting.com.ua (198.7.61.20) 0.054ms pmtu 1500
1: hosted.by.leaseweb.com (198.7.61.61) 0.337ms
1: hosted.by.leaseweb.com (198.7.61.60) 0.399ms
2: ae3.cr1.wdc1.leaseweb.net (108.59.15.120) 0.379ms
3: ash-bb1-link.telia.net (80.239.196.197) 17.066ms asymm 4
4: ash-bb4-link.telia.net (213.155.130.72) 1.198ms
5: hbg-bb2-link.telia.net (213.155.131.250) 88.118ms asymm 6
6: war-b2-link.telia.net (213.155.134.119) 106.503ms
7: ukrtelecom-ic-139714-war-b2.c.telia.net (80.239.135.46) 130.971ms asymm 8
8: no reply
9: new4.ukrtelecom.ua (82.207.79.44) 133.614ms reached
Resume: pmtu 1500 hops 9 back 52
[root @ us3 ~] # ping 82.207.79.44
PING 82.207.79.44 (82.207.79.44) 56 (84) bytes of data.
64 bytes from 82.207.79.44: icmp_seq = 1 ttl = 52 time = 130 ms
64 bytes from 82.207.79.44: icmp_seq = 2 ttl = 52 time = 130 ms
64 bytes from 82.207.79.44: icmp_seq = 3 ttl = 52 time = 130 ms
64 bytes from 82.207.79.44: icmp_seq = 4 ttl = 52 time = 130 ms
64 bytes from 82.207.79.44: icmp_seq = 5 ttl = 52 time = 131 ms
64 bytes from 82.207.79.44: icmp_seq = 6 ttl = 52 time = 131 ms
64 bytes from 82.207.79.44: icmp_seq = 7 ttl = 52 time = 131 ms
^ Z
[5] + Stopped ping 82.207.79.44
[root @ us3 ~] #



For some reason, traffic to some providers in Ukraine goes through Moscow, however, the channel is stable:

[root @ us3 ~] # tracepath o3.ua
1: us3.ua-hosting.com.ua (198.7.61.20) 0.063ms pmtu 1500
1: hosted.by.leaseweb.com (198.7.61.61) 0.419ms
1: hosted.by.leaseweb.com (198.7.61.60) 0.437ms
2: ae1.cr1.wdc1.leaseweb.net (108.59.15.116) 0.389ms
3: te2-2.msc1.wdc.leaseweb.net (217.20.125.6) 0.652ms
4: xe1-0-0.ms1.iad.leaseweb.net (217.20.125.15) 1.284ms
5: xe0-0-0.ms2.iad.leaseweb.net (217.20.125.31) 1.132ms asymm 4
6: ahn.eqx.transtelecom.net (206.126.236.233) 89.537ms asymm 5
7: msk05.transtelecom.net (188.43.7.230) 138.340ms asymm 13
8: v6.cs1-g50.kv.wnet.ua (217.20.160.103) 146.268ms asymm 10
9: v6.cs1-g50.kv.wnet.ua (217.20.160.103) 146.422ms asymm 10
10: freenet-gw.cs-leo.kv.wnet.ua (217.20.168.237) 138.373ms asymm 8
11: ua.bb.freenet.ua (89.252.0.221) 141.737ms asymm 10
12: 94.76.104.22.freenet.com.ua (94.76.104.22) 146.579ms asymm 13
13: 94.76.104.22.freenet.com.ua (94.76.104.22) 148.404ms
14: noc.freenet.com.ua (94.76.107.4) 147.120ms reached
Resume: pmtu 1500 hops 14 back 51
[root @ us3 ~] # ping 94.76.107.4
PING 94.76.107.4 (94.76.107.4) 56 (84) bytes of data.
64 bytes from 94.76.107.4: icmp_seq = 1 ttl = 51 time = 147 ms
64 bytes from 94.76.107.4: icmp_seq = 2 ttl = 51 time = 147 ms
64 bytes from 94.76.107.4: icmp_seq = 3 ttl = 51 time = 146 ms
64 bytes from 94.76.107.4: icmp_seq = 4 ttl = 51 time = 146 ms
64 bytes from 94.76.107.4: icmp_seq = 5 ttl = 51 time = 146 ms
64 bytes from 94.76.107.4: icmp_seq = 6 ttl = 51 time = 146 ms
64 bytes from 94.76.107.4: icmp_seq = 7 ttl = 51 time = 146 ms
^ Z
[7] + Stopped ping 94.76.107.4
[root @ us3 ~] #



Connectivity to Moscow:

[root @ us3 ~] # tracepath MSK-M9-Relarn-1.relarn.ru
1: us3.ua-hosting.com.ua (198.7.61.20) 0.073ms pmtu 1500
1: hosted.by.leaseweb.com (198.7.61.60) 0.414ms
1: hosted.by.leaseweb.com (198.7.61.61) 0.425ms
2: be7.cr2.wdc1.leaseweb.net (108.59.15.112) 0.762ms
3: te3-3.msc1.wdc.leaseweb.net (217.20.125.8) 0.715ms
4: xe0-0-0.ms2.iad.leaseweb.net (217.20.125.31) 1.101ms
5: ahn.eqx.transtelecom.net (206.126.236.233) 89.511ms
6: pe04.Moscow.gldn.net (79.104.225.70) 133.438ms asymm 9
7: Rosniiros-gw.transtelecom.net (217.150.63.137) 139.801ms asymm 10
8: Rosniiros-gw.transtelecom.net (217.150.63.137) 141.582ms asymm 10
9: MSK-M9-Relarn-1.relarn.ru (193.232.226.10) 130.440ms reached
Resume: pmtu 1500 hops 9 back 247
[root @ us3 ~] # ping 193.232.226.10
PING 193.232.226.10 (193.232.226.10) 56 (84) bytes of data.
64 bytes from 193.232.226.10: icmp_seq = 1 ttl = 247 time = 129 ms
64 bytes from 193.232.226.10: icmp_seq = 2 ttl = 247 time = 129 ms
64 bytes from 193.232.226.10: icmp_seq = 3 ttl = 247 time = 128 ms
64 bytes from 193.232.226.10: icmp_seq = 4 ttl = 247 time = 128 ms
64 bytes from 193.232.226.10: icmp_seq = 5 ttl = 247 time = 129 ms
64 bytes from 193.232.226.10: icmp_seq = 6 ttl = 247 time = 129 ms
64 bytes from 193.232.226.10: icmp_seq = 7 ttl = 247 time = 128 ms
^ Z
[9] + Stopped ping 193.232.226.10
[root @ us3 ~] #



Connectivity to Peter:

[root @ us3 ~] # tracepath selectel.ru
1: us3.ua-hosting.com.ua (198.7.61.20) 0.066ms pmtu 1500
1: hosted.by.leaseweb.com (198.7.61.60) 0.424ms
1: hosted.by.leaseweb.com (198.7.61.61) 0.486ms
2: be6.cr2.wdc1.leaseweb.net (108.59.15.106) 0.597ms
3: te3-3.msc2.wdc.leaseweb.net (217.20.125.12) 0.676ms
4: te3-1.msc1.wdc.leaseweb.net (217.20.125.28) 1.396ms asymm 6
5: xe0-0-0.ms2.iad.leaseweb.net (217.20.125.31) 1.172ms asymm 4
6: cat01.Frankfurt.beeline.ru (206.126.236.130) 93.560ms asymm 7
7: spb03.transtelecom.net (217.150.45.142) 130.942ms asymm 6
8: ae-01-1201.BRC1.spb.obit.ru (79.142.92.90) 126.136ms
9: gw-cust-selectel.obit.ru (217.79.3.130) 126.574ms asymm 14
10: 188.93.16.26 (188.93.16.26) 132.811ms reached
Resume: pmtu 1500 hops 10 back 49
[root @ us3 ~] # ping 188.93.16.26
PING 188.93.16.26 (188.93.16.26) 56 (84) bytes of data.
64 bytes from 188.93.16.26: icmp_seq = 1 ttl = 50 time = 135 ms
64 bytes from 188.93.16.26: icmp_seq = 2 ttl = 49 time = 138 ms
64 bytes from 188.93.16.26: icmp_seq = 3 ttl = 49 time = 139 ms
64 bytes from 188.93.16.26: icmp_seq = 4 ttl = 49 time = 139 ms
64 bytes from 188.93.16.26: icmp_seq = 5 ttl = 50 time = 135 ms
64 bytes from 188.93.16.26: icmp_seq = 6 ttl = 49 time = 135 ms
64 bytes from 188.93.16.26: icmp_seq = 7 ttl = 49 time = 139 ms
^ Z
[13] + Stopped ping 188.93.16.26
[root @ us3 ~] #



The bottom line: connectivity with Ukraine, Moscow and St. Petersburg at about the same level. Ping performance in the range of 130-150 ms. Values ​​are stable, without sharp peaks and dips.

Conclusion: Data center in the US is more appropriate to use if your resource is focused on the American audience, however, the ping values ​​for most visitors from Ukraine and the Russian Federation allow you to get quality access to sites located not only in the Netherlands, but also in the USA. The speed of loading web pages difference in connectivity will not have a strong impact. Also, the location in the United States will be attractive in law. As in the Netherlands, sites for adults are allowed, but copyrighted objects are also protected and you need to respond to complaints, like everywhere else.



For those who want to conduct their tests, I will indicate the ip-address of one of our servers in the USA: 198.7.61.20

You can request a test file for checking the speed and other interesting information in our online chat on the page with servers. You can also order a server in the US at the lowest price .

Source: https://habr.com/ru/post/191482/


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