-: Facilities support. 2 2
In this lesson, we're going to discuss the concept 3 3
of facilities and infrastructure support 4 4
for our data centers and our recovery sites. 5 5
To provide proper facility support, 6 6
it's important to consider power, cooling, 7 7
and fire suppression. 8 8
So we're going to cover uninterrupted power supplies, 9 9
power distribution units, generators, HVAC, 10 10
and fire suppression systems in this lesson. 11 11
First, we have a UPS, or uninterruptible power supply. 12 12
Now an uninterruptible power supply, 13 13
or uninterruptible power source, 14 14
is an electrical apparatus 15 15
that provides emergency power to a load 16 16
whenever the input power source or main power 17 17
is going to fail. 18 18
Most people think of these as battery backups, 19 19
but in our data centers and telecommunication closets, 20 20
we usually see devices 21 21
that contain more than just a battery backup. 22 22
For our purposes, we're going to use an UPS 23 23
that is going to provide line conditioning 24 24
and protect us from surges and spikes in power. 25 25
Our goal in using an UPS 26 26
is to make sure that we have clean reliable power. 27 27
Now an UPS is great for short duration power outages, 28 28
but they usually don't last more than about 15 to 30 minutes 29 29
because they have a relatively short battery life. 30 30
The good news is the batteries 31 31
are getting better and better every day 32 32
and their lives are getting longer and longer 33 33
in newer units. 34 34
Second, we have power distribution units or PDUs. 35 35
Now a power distribution unit 36 36
is a device fitted with multiple outputs 37 37
designed to distribute electrical power, 38 38
especially to racks of computers 39 39
and networking equipment located within our data centers. 40 40
PDUs can be rack-mounted 41 41
or they can take the form of a large cabinet. 42 42
In large data center, 43 43
you're usually going to see these large cabinets, 44 44
and in general, 45 45
there's going to be one PDU for each row of servers 46 46
and it maintains the high current circuits, 47 47
circuit breakers, 48 48
and power monitoring panels inside of them. 49 49
These PDUs can provide power protection from surges, 50 50
spikes, and brownouts, 51 51
but they are not designed 52 52
to provide full blackout protection like an UPS would 53 53
because they don't have battery backups. 54 54
Generally, a PDU be combined with an UPS or a generator 55 55
to provide that power that is needed during a blackout. 56 56
Third, we have generators. 57 57
Now large generators are usually going to be installed 58 58
outside of a data center 59 59
in order to provide us with longterm power 60 60
during a power outage inside your region. 61 61
These generators can be powered by diesel, 62 62
gasoline, or propane. 63 63
For example, at my office, 64 64
I have a 20,000 kilowatt diesel generator 65 65
that's used to provide power in case we have a power outage. 66 66
Now the big challenge with a generator though, 67 67
is that they take time to get up to speed 68 68
until they're ready to start providing power 69 69
to your devices. 70 70
They can take usually between 45 to 90 seconds. 71 71
So you usually need to pair them up 72 72
with a battery backup or UPS 73 73
as you're designing your power redundancy solution. 74 74
For example, at my office, if the power goes out, 75 75
the UPS will carry the load for up to 15 minutes. 76 76
During that time, 77 77
the generator will automatically be brought online, 78 78
usually taking 45 to 90 seconds. 79 79
Once that generator is fully online, 80 80
and providing the right stable power, 81 81
and it's ready to take the load, 82 82
the power gets shifted 83 83
from the UPS batteries to the generator, 84 84
using an automatic transfer switch or ATS. 85 85
Now once the power is restored in our area 86 86
for at least five minutes being steady, 87 87
then our ATS will actually shift power back to the grid 88 88
through our UPS unit, that battery backup, 89 89
and then shut down our generator. 90 90
Fourth, we have HVAC units. 91 91
HVAC stands for heating, ventilation, and air conditioning. 92 92
Our data centers 93 93
are going to generate a ton of heat inside of them 94 94
because of all these servers, and switches, 95 95
and routers, and firewalls, 96 96
that are doing processing inside of them. 97 97
To cool down these devices, 98 98
we need to have a good HVAC system. 99 99
Now to help with this cooling, 100 100
most data centers are going to utilize 101 101
a hot and cold aisle concept. 102 102
Now in the simplest form, 103 103
each row of servers is going to face another row of servers. 104 104
These two rows 105 105
will have the front of the servers facing each other 106 106
and the rear of the servers facing away from the aisle. 107 107
This is because the servers are designed 108 108
to push air out the rear of the device. 109 109
So the front of the servers is in the cold aisle 110 110
and the rear of the servers is in the hot aisle. 111 111
This lets us focus our HVAC systems into the hot aisles 112 112
to suck that hot air out, 113 113
cool it down, and return it back to the cold aisle, 114 114
where it can then be circulated over the servers once again. 115 115
Remember, proper cooling is important to the health 116 116
and security of our networks and our devices. 117 117
If the network devices start to overheat, 118 118
they will shut themselves down 119 119
to protect their critical components, 120 120
and if those components get overheated for too long, 121 121
permanent damage can occur 122 122
or it can decrease the life expectancy of those devices. 123 123
Now our fifth and final thing we need to discuss 124 124
is fire suppression. 125 125
In a data center, 126 126
we usually have built-in fire suppression systems. 127 127
These can include wet pipe sprinklers, 128 128
pre-action sprinklers, and special suppression systems. 129 129
Now a wet pipe system is the most basic type 130 130
of fire suppression system, 131 131
and it involves a sprinkler system and pipes 132 132
that always contain water in those pipes. 133 133
Now in a server room or data center environment, 134 134
this is kind of dangerous 135 135
because a leak in that pipe could damage your servers 136 136
that are sitting underneath them. 137 137
In general, you should avoid using a wet pipe system 138 138
in and around your data centers. 139 139
Instead, you should use a pre-action system 140 140
to minimize the risk of accidental release 141 141
if you're going to be using a wet pipe system. 142 142
With a pre-action system, 143 143
both the detector actuator 144 144
is going to work like a smoke detector, 145 145
and then there's going to be a sprinkler 146 146
that has to be tripped also 147 147
before the water is going to be released. 148 148
Again, using water in a data center, 149 149
even in a pre-action system, 150 150
is not really a good idea though, so I try to avoid it. 151 151
Instead, I like to rely on special suppression systems 152 152
for most of my data centers. 153 153
This will use something like a clean agent system. 154 154
Now a clean agent is something like halocarbon agents 155 155
or inert gases, 156 156
which released, the agents will displace the oxygen 157 157
in the room with that inert gas 158 158
and essentially suffocate the fire. 159 159
Now, the danger with using 160 160
a special suppressant system like this 161 161
is that if there's people working in your data center, 162 162
those people can suffocate 163 163
if the clean agent is being released. 164 164
So your data center needs to be equipped with an alarm 165 165
that announces when the clean agent is being released, 166 166
and you also need to make sure 167 167
there's supplemental oxygen masks available 168 168
and easily accessible 169 169
by any person who's working in that data center 170 170
whenever they hear the alarm go off 171 171
for that clean agent release. 172 172
So remember, when you're designing your data centers 173 173
and your primary work environment or your recovery sites, 174 174
you need to consider your power, 175 175
your cooling, and your fire suppression needs.