Checking the Operating Environment of the Storage Device
Check that the operating environment under which the storage device works meets associated requirements to ensure stable running of the device.
Check Method
This section describes how to check the equipment room environment. Checking the equipment room helps the maintenance personnel know the environment conditions and detect potential environment risks to prevent device faults due to environment issues.
Storage devices require a reliable operating environment. Usually, they are installed in a dedicated equipment room with a dedicated air-conditioning system and a redundant power system. Table 4-1 lists the environment check items. For the check criteria, see Check Criteria.
Item |
Check Method |
|---|---|
Temperature, humidity, and altitude |
Read the thermometer, hygrometer, and barometer in the equipment room. |
Vibration and shock |
Hire a professional organization to measure the vibration and shock on the storage system when it is working or stored. |
Particle contaminants |
Hire a professional organization to monitor the particle contaminants in the equipment room. |
Corrosive gas contaminants |
Hire a professional organization to monitor the corrosive gas contaminants in the equipment room. |
Internal rack environment |
|
Troubleshooting
- If the measured temperature or humidity falls outside the normal range, tune the air conditioners in the equipment room until the temperature or humidity falls within the normal range.
- If the power supply system fails to meet the standard, append dedicated power lines and a power transformer with sufficient capacity.
Check Criteria
This section describes the criteria for checking the storage system's operating environment.
Temperature, Humidity, and Altitude
Temperature, humidity, and altitude requirements must be met so that storage systems can correctly work or be properly preserved.
Table 4-2 lists the temperature, humidity, and altitude requirements of the storage systems.
Parameter |
Condition |
Requirement |
|---|---|---|
Temperature |
Operating temperature |
|
Temperature variation in the operating environment |
1°C (1.8°F)/min |
|
Non-operating ambient temperature |
-40°C to +70°C (-40°F to +158°F) |
|
Storage temperature (during transportation and storage with packages) |
-40°C to +70°C (-40°F to +158°F) |
|
Humidity |
Operating humidity |
10% RHa to 90% RH |
Non-operating ambient humidity |
5% RH to 95% RH |
|
Maximum humidity variation |
10%/h |
|
Storage humidity (during transportation and storage with packages) |
5% RH to 95% RH |
|
Altitude |
Operating altitude of disks |
|
Non-operating altitude of disks |
|
|
a: relative humidity (RH) |
||
Vibration and Shock
Vibration and shock requirements must be met so that storage systems can correctly work or be properly preserved.
Table 4-3 shows the vibration and shock requirements of storage systems.
Parameter |
Requirement |
|---|---|
Operating vibration |
5 to 350 Hz, PSD: 0.0002 g2/Hz, 350 to 500 Hz, -3 dB, 0.3 Grms, 3 axes, 15min/axis |
Non-operating vibration |
10 to 500 Hz, 1.49 Grms, 3 axes, 15 min/axis PSD:
|
Non-operating shock |
Half sine, 70 Gs/2 ms, 1 shock/face, total 6 faces |
Particle Contaminants
Particle contaminants and other negative environmental factors (such as abnormal temperature and relative humidity) may expose IT equipment to a higher risk of corrosive failure. This section specifies the limitation on particle contaminants with the aim at avoiding such risks.
The concentration level of particle contaminants in a data center should meet the requirements listed in the white paper entitled Gaseous and Particulate Contamination Guidelines for Data Centers published in 2011 by American Society of Heating Refrigerating and Air-conditioning Engineers (ASHRAE) Technical Committee (TC) 9.9.
ASHRAE, affiliated to International Organization for Standardization (ISO), is an international organization operated for the exclusive purpose of advancing the arts and sciences of heating, ventilation, air-conditioning, and refrigeration (HVAC & R). The Gaseous and Particulate Contamination Guidelines for Data Centers is widely accepted, which is prepared by the members of ASHRAE TC 9.9, AMD, Cisco, Cray, Dell, EMC, Hitachi, HP, IBM, Intel, Seagate, SGI, and Sun.
According to the Guidelines, particle contaminants in a data center shall reach the cleanliness of ISO 14664-1 Class 8:
- Each cubic meter contains not more than 3,520,000 particles that are greater than or equal to 0.5 μm.
- Each cubic meter contains not more than 832,000 particles that are greater than or equal to 1 μm.
- Each cubic meter contains not more than 29,300 particles that are greater than or equal to 5 μm.
It is recommended that you use an effective filter to process air flowing into the data center as well as a filtering system to periodically clean the air already in the data center.
ISO 14644-1, Cleanrooms and Associated Controlled Environments - Part 1: Classification of Air Cleanliness, is the primary global standard on air cleanliness classification. Table 4-4 gives the air cleanliness classification by particle concentration.
ISO Class |
Maximum Allowable Concentrations (Particles/m3) for Particles Equal To and Greater Than the Considered Sizes Shown Below |
|||||
|---|---|---|---|---|---|---|
- |
≥ 0.1 μm |
≥ 0.2 μm |
≥ 0.3 μm |
≥ 0.5 μm |
≥ 1 μm |
≥ 5 μm |
Class 1 |
10 |
2 |
- |
- |
- |
- |
Class 2 |
100 |
24 |
10 |
4 |
- |
- |
Class 3 |
10,00 |
237 |
102 |
35 |
8 |
- |
Class 4 |
10,000 |
2,370 |
1,020 |
352 |
83 |
- |
Class 5 |
100,000 |
23,700 |
10,200 |
3,520 |
832 |
29 |
Class 6 |
1,000,000 |
237,000 |
102,000 |
35,200 |
8,320 |
293 |
Class 7 |
- |
- |
- |
352,000 |
83,200 |
2,930 |
Class 8 |
- |
- |
- |
3,520,000 |
832,000 |
29,300 |
Class 9 |
- |
- |
- |
- |
8,320,000 |
293,000 |
Corrosive Airborne Contaminants
Corrosive airborne contaminants and other negative environmental factors (such as abnormal temperature and relative humidity) may expose IT equipment to higher risks of corrosive failure. This article specifies the limitation on corrosive airborne contaminants with an aim at avoiding such risks.
Table 4-5 lists common corrosive airborne contaminants and their sources.
Symbol |
Sources |
|---|---|
H2S |
Geothermal emissions, microbiological activities, fossil fuel processing, wood rot, sewage treatment |
SO2, SO3 |
Coal combustion, petroleum products, automobile emissions, ore smelting, sulfuric acid manufacture |
S |
Foundries, sulfur manufacture, volcanoes |
HF |
Fertilizer manufacture, aluminum manufacture, ceramics manufacture, steel manufacture, electronics device manufacture |
NOX |
Automobile emissions, fossil fuel combustion, chemical industry |
NH3 |
Microbiological activities, sewage, fertilizer manufacture, geothermal emissions, refrigeration equipment |
C |
Incomplete combustion (aerosol constituent), foundry |
CO |
Combustion, automobile emissions, microbiological activities, tree rot |
Cl2, ClO2 |
Chlorine manufacture, aluminum manufacture, zinc manufacture, refuse decomposition |
HCl |
Automobile emissions, combustion, forest fire, oceanic processes, polymer combustion |
HBr, HI |
Automobile emissions |
O3 |
Atmospheric photochemical processes mainly involving nitrogen oxides and oxygenated hydrocarbons |
CNHN |
Automobile emissions, animal waste, sewage, tree rot |
The concentration level of corrosive airborne contaminants in a data center should meet the requirements listed in the white paper entitled Gaseous and Particulate Contamination Guidelines for Data Centers published in 2011 by ASHRAE TC 9.9.
According to the Guidelines, corrosive airborne contaminants in a data center should meet the following requirements:
- Copper corrosion rate
Less than 300 Å/month, severity level G1 per ANSI/ISA-71.04-1985
- Silver corrosion rate
Less than 200 Å/month
Å, or angstrom, is a unit of length. One Å is equal to 1/10,000,000,000 meter.
According to ANSI/ISA-71.04-1985 Environmental Conditions for Process Measurement and Control Systems: Airborne Contaminants, the gaseous corrosivity levels are G1 (mild), G2 (moderate), G3 (harsh), and GX (severe), as described in Table 4-6.
Severity Level |
Copper Reactivity Level |
Description |
|---|---|---|
G1 (mild) |
300 Å/month |
An environment sufficiently well-controlled such that corrosion is not a factor in determining equipment reliability. |
G2 (moderate) |
300 Å/month to 1000 Å/month |
An environment in which the effects of corrosion are measurable and may be a factor in determining equipment reliability. |
G3 (harsh) |
1000 Å/month to 2000 Å/month |
An environment in which there is high probability that corrosion will occur. |
GX (severe) |
> 2000 Å/month |
An environment in which only specially designed and packaged equipment would be expected to survive. |
See Table 4-7 for the copper and silver corrosion rate requirements.
Group |
Gas |
Unit |
Concentration |
|---|---|---|---|
Group A |
H2S |
ppba |
< 3 |
SO2 |
ppb |
< 10 |
|
Cl2 |
ppb |
< 1 |
|
NO2 |
ppb |
< 50 |
|
Group B |
HF |
ppb |
< 1 |
NH3 |
ppb |
< 500 |
|
O3 |
ppb |
< 2 |
|
a: Part per billion (ppb) is the number of units of mass of a contaminant per billion units of total mass. |
|||
Group A and group B are common gas groups in a data center. The concentration limits of Group A or group B that correspond to copper reactivity level G1 are calculated based on the premise that relative humidity in the data center is lower than 50% and that the gases in the group interact with each other. A 10% of increase in the relative humidity will heighten the gaseous corrosivity level by 1.
Corrosion is not determined by a single factor, but by comprehensive environmental factors such as temperature, relative humidity, corrosive airborne contaminants, and ventilation. Any of the environmental factors may affect the gaseous corrosivity level. Therefore, the concentration limitation values specified in the previous table are for reference only.
Checking Racks
Properly installed racks of the storage device help ensure the stable and long-term running of the storage device. Check rack conditions periodically to reduce device failure possibilities.
Impact on the System
The storage device imposes demanding requirements on rack conditions. An improperly installed rack impairs the proper running of the storage device.
Tools and Materials
Ensure that the tools and materials for checking rack conditions are available. The required tools include binding straps, an electroprobe, and a multimeter.
Reference Standard
Table 4-8 lists the items and standards for checking rack conditions.
Check Item |
Standard |
|---|---|
General layout of cables |
Power cables (with strong electrical current) and service cables (with weak electrical current) are laid on different sides of a rack. |
Layout of power cables |
Power cables are laid out orderly and arranged in a similar manner to power cables on other racks. |
Layout of service cables |
Service cables are laid out orderly and arranged in a similar manner to service cables on other racks. |
Cable labeling |
Labels are clearly marked and securely attached. |
Empty slot |
Empty slots are covered with filler panels for proper heat dissipation and a neat appearance. |
Power cable plug |
One end of each power cable is fully plugged into an external power socket and the other end into a storage device socket. |
Signal cable plug |
Signal cables are fully plugged into appropriate device ports. |
Ground cable |
One end of each ground cable is secured by a ground clip and the other end is fastened to a rack ground terminal. |
Power cable |
Two groups of power cables are available for redundancy. |
Front-end port connection |
|
Management network port connection |
One end of each management network cable is fully plugged into a storage device management network port and the other end is connected to the network where the maintenance terminal resides. |
