tier1和tier2

A data center is a facility used to house computer systems and provides the required environment to these systems. The old day’s data center was a bit luxury but today’s situations a lot of SMB’s have data centers.

数据中心是用于容纳计算机系统的设施，并为这些系统提供所需的环境。过去的数据中心有点豪华，但是今天的情况是，许多SMB都拥有数据中心。

数据中心问题 (Problems Of Data Centers)

We expect a Windows server to run forever but it’s not. An electricity outage may bring down the system if the data center has not enough UPS power. A bug in the network infrastructure will bring down the network. We can say a lot of different scenarios that may affect the health and expected operation of the data center.

我们希望Windows服务器可以永远运行，但事实并非如此。如果数据中心的UPS电源不足，则停电可能会导致系统停机。网络基础结构中的错误将导致网络瘫痪。我们可以说很多不同的情况都可能影响数据中心的运行状况和预期运行。

层级 (Tiers)

We can not prevent the unexpected events but lower the effects of their operations by making plans and redundancy. Also, we can meter the outage level and duration by setting limits. But Telecommunication Industry Association (TIA) all ready did this with start ANSI/TIA-942. In this standard, there are four levels to meter the outage. The level are called Tiers like Tier-1, Tier-2, Tier-3, Tier-4 . We will look in detail below for these Tiers.

我们无法防止意外事件，但会通过制定计划和冗余来降低意外事件的影响。另外，我们可以通过设置限制来计量中断级别和持续时间。但是电信行业协会(TIA)都已经做好了从ANSI / TIA-942开始的准备。在此标准中，有四个级别来计量中断。该级别称为第1层，第2层，第3层，第4层等层。我们将在下面详细介绍这些层。

1级 (Tier-1)

The lowest level of the ANSI/TIA-942 standard. A single non-redundant distribution path serving to the IT equipment is required at this level. Also, non-redundant capacity components are used. Basic site infrastructure expected availability is 99.671% which will allow 1729 minutes or 28.8 hours outage

ANSI / TIA-942标准的最低级别。在此级别上，需要一条服务于IT设备的单一非冗余分发路径。同样，使用非冗余容量组件。基本站点基础结构的预期可用性为99.671％，这将允许1729分钟或28.8小时停机

2级(Tier-2)

Meets or exceeds all Tier-1 requirements. Also redundant site infrastructure availability is 99.741% which is 1361 minutes or 22.6 hours outage.

达到或超过所有1级要求。此外，冗余站点基础结构可用性为99.741％，即1361分钟或22.6小时停机。

3级 (Tier-3)

Meets and exceeds all Tiers-2 requirements. Also as a plus, multiple independent distribution paths are required. All IT equipment must be dual-powered. Uptime percentage is 99.982% which means a maximum of 94 minutes. 1.5 hours outage.

符合并超过所有Tiers-2要求。另外，还需要多个独立的分发路径。所有IT设备都必须是双电源的。正常运行时间百分比为99.982％，这意味着最长为94分钟。停电1.5小时。

4级 (Tier-4)

Meets or exceeds all Tier-3 requirements. All cooling equipment is independently dual-powered. Uptime percentage is 99.995% which is equal to 26 minutes or 0.4 hours outage.

达到或超过所有Tier-3要求。所有冷却设备均独立采用双电源供电。正常运行时间百分比为99.995％，等于26分钟或0.4小时停机。

翻译自: https://www.poftut.com/datacenter-tiers-tier1-tier2-tier3-tier4/