Comments on: Explain: Tier 1 / Tier 2 / Tier 3 / Tier 4 Data Center

By: Raghav

Raghav — Wed, 08 Feb 2012 07:06:36 +0000

Hi Kindly share me the cooling type used in DC.

By: Scott Payton

Scott Payton — Wed, 01 Feb 2012 17:44:58 +0000

BejoyN,
Since this thread about DC has gotten “out of hand” on a Unix site, can you please come to Tek-Tips (www.tek-tips.com) and ask these questions in the Data Center Discussion forum? I’m trying to corral all the information into one site, where others can benefit from it.
Repost there, and I’ll answer all your questions.
-S

By: BejoyN

BejoyN — Wed, 01 Feb 2012 15:13:34 +0000

Hi Scott,

We are in the process of setting up a data centre in Africa. We are hoping to achieve a Tier III status on this data centre as we will have redudant power supply (Power from the Electricity company Sub Station + 2 x Standby Generators + UPS’s to protect the racks and equipment hosted in the racks), Redundant Data Connectivity (Fibre connectivity + Satelllite for Failover) and Redundant Cooling within the data centre (two cooling units in case of failure). Now iv been reading so many articles online and has proven almost impossible to understand if this actually does meet the Tier III Standard or it will only meet a Tier II.

I would also like to know how you actually get the certification done once your data centre is built? Is there a specific organisation that you need to contact and they do the assessment and certify accordingly?

Lastly, regarding the cooling within the data centre. Many have indicated that water based chiller systems are more appropriate but others are dead against water based systems and suggest Gas based systems due to power efficiency especially in countries where the Lime content is high in the water.

Would be great to get your feedback.

Thanks

Bejoy

By: Scott Payton

Scott Payton — Wed, 25 Jan 2012 04:08:35 +0000

Sun,
Tier III (or Tier 3) does not specify the type of fiber termination. It’s not part of the Tier standard. There are likely opinions on “best practice” for fiber termination in Tier standards.

This whole thread seems to be way off topic of UNIX world… I would suggest visiting Tek-Tips (www.tek-tips.com) and join my moderated DC forum there (Data Center Discussion).
Best regards,
-S

By: sun

sun — Wed, 18 Jan 2012 19:07:09 +0000

What kind of fiber termination method is using for TIR 3 datacetres.
Please give me an idea

By: Scott Payton

Scott Payton — Mon, 16 Jan 2012 23:46:48 +0000

Nanda,
Two issues here… There are two “standards” that utilize the term “Tier” as their rating system. Uptime Institute use Tier I – Tier IV (roman numeral) while TIA-942 utilizes Tier 1 – Tier 4 (Arabic numbers).
There are no certifying bodies for TIA-942. Several companies may claim to do “TIA-942 certification” but this is meaningless. At best they can compare as-built to TIA criteria, and assess that it meets or does not meet in their opinion.
For Uptime Institute, only Uptime Institute Professional Services can provide an official Certification. This is regardless of the Tier level, so they are the same body to certify a DC as Tier I as Tier III (or any other Tier level).
Hope that helps.
Cheers,
-S

By: Scott Payton

Scott Payton — Mon, 16 Jan 2012 23:43:22 +0000

Vinay,
Please read my full post. If we are discussing Uptime Institute Tier Standard: Topology, from the 2010 revision, “Dual Power Source”, if we are referring to utility power source, is not required. In fact, for any Tier I – Tier IV, NO utility power sources are required, though they are frequently utilized as a low-cost alternative to commercial power.
If you are comparing to Appendix G of TIA-942, in their suggested “check list”, of DC items, Tier 3 and Tier 4 of the 2010 list do require utility power source redundancy (be definition they define Tier 3 as N+1 Utility feed, which means minimum 2, but could require more, and Tier 4 needing 2N power feeds from separate utility substations (meaning, 4 feeds!) which in my view has no value, as power grids will fail, and regardless of the number of stations providing their power, the grid can still fail. This results in millions of dollars in investment, and yields no value when the power goes out.
-S

By: Vinay k

Vinay k — Mon, 16 Jan 2012 07:39:31 +0000

Hi Janice,

According to my knowledge. You need to have Dual Power Source for TIII rating DC.

Thanks,
Vinay Kumra

By: D NANDA

D NANDA — Wed, 28 Dec 2011 18:14:49 +0000

who will be the certification body for Tier III & Tier IV , Any consultant / Expert can issue the certificate of Tier III & Tier IV
what are the standards to follow for Tier III & Tier IV certification for data centre
do you hv any checklist for that

By: Mohammed Smith

Mohammed Smith — Tue, 11 Oct 2011 20:50:14 +0000

Sir Scott,
Kindly do the needful. Answer these brilliant questions of brilliance.

By: Scott Payton

Scott Payton — Mon, 05 Sep 2011 16:58:30 +0000

Janice,
There are a few parts to this.
First, let’s identify the standard. You mention both Tier III and Tier 3. First is designation for Tier under Uptime Institute. The second one (with Arabic number) is TIA-942 designation.
I’m going to assume in this case, we are talking about Uptime Institute. Under Uptime Institute, you are asking “Dual Power Supply” inside or outside. The answer here, is both from a certain point, and probably more than just what your question is asking.
Let me try to clarify.
Tier III (or 3) in both cases is defined as “Concurrently Maintainable”. What that means in this case is, for your power system you must have the ability to remain under critical load (N) while performing maintenance (on your power or cooling systems). For power, that will mean you will likely have A and B power feed, which may or may not both be active at the same time. This will mean you will have at least N+1 UPS (usually on each feed, but there are other options, I’m just using this as an example) which would give your UPS (2)N+1 meaning you have N+1 on A and N+1 on B power feeds. Going back to the source however, this can be a little un-obvious. The reason being is for Tier III and IV sites, the generator set is considered the primary power plant. It is not necessary to have 2 (or even 1) utility power feed to meet the Tier objective, so long as the generator plant is properly setup and configured. I’ll skip that detail for now, as it’s going in the different direction to your question.
So, from power source (Gen or Utility) you need redundant components (Switches, UPS, Batteries) and redundant pathways for power (At least one active, the other passive, though both active is also allowed), leading to your critical IT load, as well as to your Mechanical Load (though Mechanical Load does not have to be on the UPS for Tier III). The last “gotcha” in the Tier III power issue is dual corded IT equipment. The IT gear itself (Server, Switch, SAN, data circuit) must be dual corded, with one plugged to A feed and one to B feed. If only single cord (as some data circuit gear), then it has to be plugged to an ATS or STS in-rack that then has dual feed cord connection to A and B power feeds.
TIA is not terribly different, as for the largest part they have borrowed an older Uptime Standard for Tier system which follows about 90% of the Uptime standard. Dual corded in TIA is also required. However, under the new TIA-942-2 standard, Utility Power Feeds for Tier III are designated as N+1 (Which would mean, you would need at least 2 in most cases, or more if any 1 utility feed was not enough power to carry the DC load). The rest of the power issues going forward from that point are the same as Uptime Institute.

If you need more clarity around the engine generator plant let me know but that didn’t seem to be your question, and there are significant gaps in this space between the two standards.

I know it’s a little convoluted, and I hope this helps.
Best regards,
Scott Payton ATS, CDCS

By: Janice.

Janice. — Mon, 05 Sep 2011 14:55:19 +0000

Please can anyone clarify this? Do you have to have a dual power supply into the site to be Tier III compliant or can you be Tier 3 if you have redundancy inside the building?

By: Prasen

Prasen — Wed, 29 Jun 2011 13:17:10 +0000

Hi Ambrose.

I am in to Racks IT solutions , And also promoting inrow and licquid colling solution.

Can u please suggest me what are the level to get certified data centre associates.

Like APC offering DU0-001 which is best

By: Scott Payton

Scott Payton — Sat, 21 May 2011 14:12:13 +0000

Mohan,
The questions you ask are too extensive without understanding the business objectives. Plus, this kind of thing is what consultants get paid to do… it’s unlikely you will get a “full reply” about all the items you mention. The level of effort to respond in a meaningful way to all of this would take weeks to explain.
If you have some questions, you can email me directly at spayton at gmail.com I will give you guidance, but without understanding what you’re trying to achieve, this is like asking someone to explain, in full detail, how to construct a 140 story skyscraper, with no more detail then that.

By: mohan

mohan — Sat, 21 May 2011 09:05:37 +0000

Hai,
Those who are brilliant in datacentre technology share your briliance for the foll.

1.Rack allocation for server,router,switch,kvm and future expansion how?
2.How the building space chosen?
3.How the cooling chosen ? i.e ( centralised or packaged unit etc..)
4.Any std to be for maintain for data cable laying,Termination of I/o,testing etc.?
5.How electrical power is calculated for rack,Ac,lights,ups,gensets any specific rules or calculation for those items.?
6.raised wooden flooring specification and std.?
7.security system for camera , fire alarm,access control type etc to be explain.if any std pls explain.?
8.false flooring type and specification for the same.?
9.Lighting type,PDB,LDB,MDB etc to explain?

pls share your brilliance,

Thanks with regards,

p.mohan

By: mohan

mohan — Sat, 21 May 2011 08:45:15 +0000

Hai friends i am going to learn CDCP COURSE .can anyone help me for sample question and documentation.If any site available.pls let me know.

By: Scott Payton

Scott Payton — Thu, 14 Apr 2011 09:05:08 +0000

Actually, this article is very misleading, and fraught with mistakes and inaccuracies (at best).

Tier , to answer Pascal’s question, refers to the gap between level of capability between each of the DC benchmarks. It’s not a “magic” term. (You could say, Tier, Level, Category, Rank… they all mean the same thing, but the industry has adopted “Tier” as the terminology to use for DC capability).

None of the Tier ranking systems (Uptime, BICSI, TIA) “guarantee” any % of uptime. They are an indicator of how likely your uptime will be, and how one should benchmark against it. Where this all goes horribly wrong, is the Tier rating for all these systems takes into account only the “Built” specification. None of them consider (at Tier rating) how a site is maintained. (Uptime now address this with Tier Standard: Operational Sustainability). So no Design or Redundancy can guarantee a % of availability.

Regarding Uptime’s Tier, this really is focused on: “Power in, Heat out”. These references to redundant storage, servers and coms is not part of the Tier classification, beyond the need for dual-corded systems in Tier III and Tier IV. (Note also Uptime use Roman Numeral, not Arabic for classification. This is because there is no “Tier III.6″ or “Tier II.v”)

For Tier III and IV, it is also necessary to have redundant generators that are Continuous Rated (as opposed to Prime or Standby rated). And Tier IV requires compartmentalization of capacity systems to no more than R (redundant) per space (2 hour fire-rated rooms).

BICSI 002-2010 was just released last year. I’m in the midst of reading it, but I’m disappointed that it has a heavy leaning to US implementations. I’m not calling it “US centric”, but there cases or references (such as site selection) have all US maps and site data on them.

TIA-942 addresses data cabling in data centers. There is no certification of a site to “TIA”, where there is a certification to “Tier Rating” with Uptime. TIA-942 has a number of “Tier” data in its appendices, but this isn’t really a rating/ranking system that has a measurable certification, more like ITIL, where you can be “ITIL compliant” but there is not “ITIL certified”. It is the same for TIA.

By: Pascal Bohni

Pascal Bohni — Tue, 08 Mar 2011 17:05:51 +0000

What is the definition of the expression “Tier”?
Any ideas?

By: Mohammed Moosa Hussain

Mohammed Moosa Hussain — Wed, 11 Aug 2010 20:58:16 +0000

i am a data center specialist i installed so many system i need the knowledge of tier 4 cdcd, cdcdp,BICSI,RCDD,ATD

By: Buhan

Buhan — Thu, 27 May 2010 17:58:02 +0000

Can a datacenter remove redundant data or should we keep it? I have a datacenter m&o job interview and need to know as fast as the reply comes.