Cisco MDS 9000 Series Instruction Manual

Installing the Cisco MDS 9148T Switch
This chapter describes how to install a Cisco MDS 9148T switch and its components.
Before you install, operate, or service the system, see the Regulatory Compliance and Safety Information for
the Cisco MDS 9000 Family document for important safety information.
This unit is intended for installation in restricted access areas. A restricted access area can be accessed
only through the use of a special tool, lock and key, or other means of security. Statement 1017
Warning
Only trained and qualified personnel should be allowed to install, replace, or service this equipment.
Statement 1030
Warning
•Preinstallation, on page 1
•Installing the Switch, on page 8
•Grounding the Switch, on page 15
•Installing and Removing Components, on page 16
Preinstallation
Cisco MDS 9000 Series Telco and EIA Shelf Bracket
The optional Telco and EIA Shelf Bracket Kit (part number DS-SHELF=) can temporarily or permanently
support the Cisco MDS 9148T switch during installation. After the front rack-mount brackets are securely
attached to the rack-mounting rails, the shelf bracket can be removed.
The Telco and EIA Shelf Bracket kit supports the following configurations:
• A Cisco MDS 9148T Switch in a two-post Telco rack
• A Cisco MDS 9148T Switch in a four-post EIA rack
Installing the Cisco MDS 9148T Switch
1

Telco and EIA Shelf Bracket optional kit is not provided with the switch; to order the kit, contact your switch
supplier.
Note
This section describes the procedure for installing a Cisco MDS 9148T switch in a rack or cabinet using the
optional Telco and EIA Shelf Bracket Kit.
Shelf-Installation Guidelines
• If the rack is on wheels, ensure that the brakes are engaged or the rack is otherwise stabilized.
• If you are installing this kit in an EIA rack, attach the shelf to all four rack-mounting posts; the EIA posts
may not be thick enough to prevent flexing of shelf brackets if only two posts are used.
Caution
Before Installing the Shelf Brackets
Before installing the shelf brackets, inspect the contents of your kit. The following table lists the contents of
the shelf bracket kit:
Part DescriptionQuantity
Slider brackets2
Shelf brackets2
Crossbar1
10-32 x 3/8-in. Phillips pan-head screws2
12-24 x 3/4-in. Phillips screws16
10-24 x 3/4-in. Phillips screws16
Required Equipment
You need the following equipment for this installation:
• Number 2 Phillips screwdriver
• Tape measure and level (to ensure that shelf brackets are at level with each other)
Installing the Shelf Bracket Kit into a Two-Post Telco Rack
The following figure shows the installation of the shelf bracket kit into a two-post Telco rack:
Installing the Cisco MDS 9148T Switch
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Installing the Cisco MDS 9148T Switch
Shelf-Installation Guidelines

Figure 1: Installing the Shelf Bracket Kit into a Telco Rack
10-32 screws3Rack-mounting post1
Crossbar4Shelf bracket2
To install the shelf brackets in a Telco rack, follow these steps:
Step 1 Position a shelf bracket inside a rack-mounting post as shown in Figure 1: Installing the Shelf Bracket Kit into a Telco
Rack, on page 3 and align the screw holes at the front of the shelf bracket with the holes in the rack-mounting post.
Then, attach the shelf bracket to the rack-mounting post using a minimum of four 12-24 or 10-24 screws.
The bottom hole of the shelf bracket should align with the bottom hole (the hole immediately above the 1/2
in. spacing) of a rack unit on the rack-mounting post.
Note
Step 2 Repeat Step 1 with the other shelf brackets.
Step 3 Verify that the shelf brackets are at the same height (using the level or tape measure, as desired).
Step 4 Attach the crossbar to the rear of the shelf brackets, as shown in Figure 1: Installing the Shelf Bracket Kit into a Telco
Rack, on page 3, using the 10-32 screws.
Installing the Shelf Bracket Kit into a Four-Post EIA Rack
The following figure shows the installation of the shelf bracket kit into a four-post EIA rack:
Installing the Cisco MDS 9148T Switch
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Installing the Cisco MDS 9148T Switch
Installing the Shelf Bracket Kit into a Four-Post EIA Rack

Figure 2: Installing the Shelf Bracket Kit into an EIA Rack
Crossbar4Rack-mounting post1
10-32 screws5Shelf bracket2
Slider post3
To install the shelf brackets in an EIA rack, follow these steps:
Step 1 Position a shelf bracket inside the rack-mounting posts, as shown in Figure 2: Installing the Shelf Bracket Kit into an
EIA Rack, on page 4. Align the screw holes at the front of the shelf bracket with the holes in the front rack-mounting
post. Then, attach the shelf bracket to the front rack-mounting post using a minimum of four 12-24 or 10-24 screws.
The bottom hole of the shelf bracket should align with the bottom hole (the hole immediately above the 1/2
in. spacing) of a rack unit on the rack-mounting post.
Note
Step 2 Repeat Step 1 with the other shelf brackets.
Step 3 Verify that the shelf brackets are at the same height (using the level or tape measure, as desired).
Step 4 Attach the crossbar to the shelf brackets, as shown in Figure 2: Installing the Shelf Bracket Kit into an EIA Rack, on page
4, using the 10-32 screws.
Step 5 Insert the slider posts into the shelf brackets, as shown in Figure 2: Installing the Shelf Bracket Kit into an EIA Rack, on
page 4. Attach them to the rear rack-mounting posts, using a minimum of four 12-24 or 10-24 screws.
Installing the Cisco MDS 9148T Switch
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Installing the Cisco MDS 9148T Switch
Installing the Shelf Bracket Kit into a Four-Post EIA Rack

Preinstallation Guidelines
Airflow Considerations
The switch comes with fan modules and power supply units that have either port-side intake or port-side
exhaust airflow for cooling the switch. If you are orienting the switch with the FC ports facing a cold aisle,
make sure that the switch has a port-side intake fan and power supply modules with red colorings. If you are
orienting the switch with the fan and power supply modules facing a cold aisle, make sure that the switch has
port-side exhaust fan and power supply units with blue colorings. All fan modules and power-supply modules
must have the same direction of airflow.
Connection Guidelines for AC-Powered Systems
To connect to the Cisco MDS 9396T switch AC power supply units to the site power source, follow these
guidelines:
• For power redundancy, each power supply should be connected to a separate power feed (at a minimum,
separate branch circuits).
• Circuits should be sized according to local and national codes.
• The AC power receptacles that are used to power the chassis must be the grounding type. The grounding
conductors that connect to the receptacles should connect to protective earth ground in the service
equipment.
Installation Guidelines
Follow these guidelines when installing the Cisco MDS 9148T switch:
• Each new switch requires a license. See the Cisco MDS 9000 Family NX-OS Licensing Guide for
instructions on installing a license.
• Plan your site configuration and prepare the site before installing the switch.
• Ensure that there is adequate space around the switch to allow for servicing the switch and for adequate
airflow. The airflow requirements are listed the Technical Specifications section.
• Ensure that you are positioning the switch in a rack so that it takes in cold air from the cold aisle and
exhausts air to the hot aisle. For more information, see the Airflow Considerations, on page 5 section.
• Ensure that the air-conditioning meets the heat dissipation requirements listed in the Technical
Specifications section.
• Ensure that the cabinet or rack meets the requirements listed in the Cabinet and Rack Installation section.
• Ensure that the chassis is adequately grounded. If the switch is not mounted in a grounded rack, we
recommend that you connect both the system ground on the chassis and the site power ground to an earth
ground.
• Ensure that the site power meets the power requirements listed in the Technical Specifications section.
If available, you can use an uninterruptible power supply (UPS) to protect against power failures.
Installing the Cisco MDS 9148T Switch
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Installing the Cisco MDS 9148T Switch
Preinstallation Guidelines

Avoid UPS types that use ferro-resonant technology. These UPS types can become
unstable with systems such as the Cisco MDS 9000 Series, triggered by substantial
current draw fluctuations due to fluctuating data traffic patterns.
Caution
• Ensure that electrical circuits are sized according to local and national codes.
For North America, the 650 W power supplies require a 15 A circuit. If you are using a 200 or 240 VAC
power source in North America, the circuit must be protected by a two-pole circuit breaker.
To prevent loss of input power, ensure that the total maximum loads on the circuits
supplying power to the switch are within the electrical current ratings for circuit
for wiring and breakers.
Caution
Unpacking and Inspecting the Switch
When handling switch components, wear an ESD strap and handle modules using only the carrier edges.
Caution
Retain the shipping container in case the chassis has to be shipped in the future.
Tip
The switch is thoroughly inspected before shipment. If any damage occurs during transportation, or if any
item is missing, contact your customer representative immediately. If you purchased Cisco support through
a Cisco reseller, contact the reseller directly. If you purchased support directly from Cisco, contact Cisco
Technical Support.
Note
To inspect the shipment, follow these steps:
1. Compare the shipment to the equipment list provided by your customer service representative and verify
that you have received all items, including the following:
• Grounding lug kit
• Rack-mount kit
• ESD wrist strap
• Cables and connectors
• Optional items, if any, ordered
2. Check for damage and report any discrepancies or damage, to your customer service representative. Have
the following information ready:
• Invoice number of shipper (see packing slip)
Installing the Cisco MDS 9148T Switch
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Installing the Cisco MDS 9148T Switch
Unpacking and Inspecting the Switch

• Model and serial number of the damaged unit
• Description of damage
• Effect of damage on the installation
3. Check if all the power supplies and the fan trays have the expected direction of airflow. Port-side intake
airflow modules have a red coloring, and port-side exhaust airflow modules have blue coloring. For more
information, see the Power Supplies and Fan Modules sections.
NEBS Compliance
In case of port-side intake airflow, the chassis is not Network Equipment-Building System (NEBS) compliant
by default. To be NEBS compliant, install the NEBS kit by performing these steps:
1. Install the NEBS rack-mount brackets onto the switch.
2. Install the NEBS air baffle by aligning the notches on the baffle with the slots on the brackets and sliding
the ends of the baffle so that the baffle locks into place.
Figure 3: NEBS Kit for 2-Post Installation
Installing the Cisco MDS 9148T Switch
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Installing the Cisco MDS 9148T Switch
NEBS Compliance

Figure 4: NEBS Kit for 4-Post Installation
notch3NEBS air baffle1
slot4NEBS rack-mount brackets2
For more information on how to install the switch, see the Installing the Switch in a 4-Post Rack and Installing
the Switch into a 2-Post Rack.
Installing the Switch
This section describes how to use the rack mount kit to install the Cisco MDS 9148T switch into a cabinet or
rack that meets the requirements described in the Cabinet and Rack Requirements section.
Installing the Switch in a 4-Post Rack
To install the switch, you must attach the front and rear mounting guides to the switch, install the slider rails
on the rear of the rack, slide the switch into the slider rails, and secure the switch to the front of the rack.
Typically, the front of the rack is the side that is easiest to access for maintenance.
Before you begin
• Inspect the switch shipment to ensure that you have everything you ordered.
• Make sure that the switch rack-mount kit includes the following parts:
Installing the Cisco MDS 9148T Switch
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Installing the Cisco MDS 9148T Switch
Installing the Switch

• Rack-mount brackets (2)
• Rack-mount guides (2)
• Slider rails (2)
• M4 x 0.7 x 8-mm Phillips countersink screws (12)
• The rack is installed and secured to its location.
• Determine how you want to set up your switch:
1. Determine which end of the chassis is to be located in the cold aisle as follows:
a. If the switch has port-side intake modules (fan modules and power supply units with red coloring),
position the switch so that its ports are in the cold aisle.
b. If the switch has port-side exhaust modules (fan modules and power supply units with blue
coloring), position the switch so that its fan modules and power supply units are in the cold aisle.
2. Determine which way the chassis should slide in and out of the rack—port-side entry first or rear-side
entry first. You might consider whether the front or back of the rack provides better clearance for
maneuvering the chassis in and out during installation and servicing. The end that needs to enter the
rack first requires the guides and the other end the brackets.
Step 1 Install two rack-mount brackets to the switch as follows:
a. Position a rack-mount bracket so that three of its screw holes are aligned to the screw holes on the side of the chassis.
You can align any three of the holes in the rack-mount bracket to three of the screw holes on the side of the chassis.
The holes that you use depend on the requirements of your rack and the amount of clearance. For more information
on clearance, see the General Requirements for Cabinets and Racks.
b. You can install the rack-mount bracket either at the front or rear of the chassis. The choice is determined by which
end of the chassis will be inserted into the rack first. If the rear end of the chassis is to be inserted first, then mount
the brackets on the front of the chassis, and vice versa.
Installing the Cisco MDS 9148T Switch
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Installing the Cisco MDS 9148T Switch
Installing the Switch in a 4-Post Rack

Figure 5: Installing Rack-Mount Brackets on the Front Side of the Chassis
Rack-mount2.M4 screws1.
c. Secure the rack-mount bracket to the chassis using the three M4 screws and tighten each screw to 12 in-lb (1.36 N·m)
of torque.
d. Repeat Step 1 for the other rack-mount bracket on the other side of the switch, and be sure to position it in the same
distance from the front of the switch.
Step 2 If you are installing the chassis into an ungrounded rack, you must attach a customer-supplied grounding wire to the
chassis. However, if you are installing the chassis into a grounded rack, you can skip this step.
Step 3 Install the slider rails into the rack or cabinet, as follows:
a. Determine which two posts of the rack or cabinet you should use for the slider rails. Of the four vertical posts in the
rack or cabinet, two will be used for the rack-mount brackets, and the other two posts will have the slider rails.
b. Position a slider rail at the desired level side of the rack and use two 12-24 screws or two 10-32 screws, depending
on the rack thread type, to attach the slider rail to the rack. Tighten the 12-24 screws to 30 in-lb (3.39 N·m) of torque,
or tighten the 10-32 screws to 20 in-lb (2.26 N·m) of torque.
c. Repeat Step 2 to attach the other slider rail to the other side of the rack.
To make sure that the slider rails are at the same level, you should use a level tool or tape measure, or carefully count
the screw holes in the vertical mounting posts.
Step 4 Insert the switch into the rack and attach it as follows:
Installing the Cisco MDS 9148T Switch
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Installing the Cisco MDS 9148T Switch
Installing the Switch in a 4-Post Rack

Chassis3.Slider rails1.
rack-mount screws2.
a. Holding the switch with both hands, position the two rack-mount guides on the switch between the rack or cabinet
posts that do not have slider rails attached to them.
b. Align the two rack-mount guides on either side of the switch with the slider rails installed in the rack. Slide the guides
onto the slider rails, and then gently slide the switch all the way into the rack until the brackets come in contact with
two rack or cabinet posts.
If you attached a grounding cable to the chassis, you will need to flex one of the rack-mount posts slightly
to allow the grounding lug to go behind the post.
Note
c. Holding the chassis level, insert two screws (12-24 or 10-32, depending on the rack type) into each of the two brackets
(using a total of four screws), and into the cage nuts or threaded holes in the rack or cabinet posts.
d. Tighten the 10-32 screws to 20 in-lb (2.26 N·m), or tighten the 12-24 screws to 30 in-lb (3.39 N·m).
Step 5 If you have attached a grounding wire to the chassis grounding pad, connect the other end of the wire to the facility
ground.
Installing the Cisco MDS 9148T Switch
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Installing the Cisco MDS 9148T Switch
Installing the Switch in a 4-Post Rack

Installing the Switch into a 2-Post Rack
Before you begin
• Determine how you want to set up your switch:
• Determine which end of the chassis is to be located in the cold aisle as follows:
1. If the switch has port-side intake modules (fan modules and power supply units with red coloring),
position the switch so that its ports are in the cold aisle.
2. If the switch has port-side exhaust modules (fan modules and power supply units with blue
coloring), position the switch so that its fan modules and power supply units are in the cold
aisle.
•Determine which way the chassis should slide in and out of the rack—port side entry first or rear-side
entry first. You might consider whether the front or back of the rack provides better clearance for
maneuvering the chassis in and out during installation and servicing. The end that needs to enter
the rack first requires the guides and the other end the brackets.
Step 1 Install two rack–mount brackets onto the switch as follows:
a. Position a rack-mount bracket so that four of its screw holes are aligned to the screw holes on the side of the chassis.
You can align any four of the holes in the rack-mount bracket to four of the six screw holes on the side of the chassis.
The holes that you use depend on the requirements of your rack and the amount of clearance. For more information
on clearance, see the General Requirements for Cabinets and Racks.
b. You can install the rack-mount bracket either at the front or rear of the chassis. The choice is determined by which
end of the chassis will be inserted into the rack first. If the rear end of the chassis is to be inserted first, then mount
the brackets on the front of the chassis, and vice versa.
Installing the Cisco MDS 9148T Switch
12
Installing the Cisco MDS 9148T Switch
Installing the Switch into a 2-Post Rack

Figure 6: Installing Rack-Mount Brackets on the Front Side of the Chassis
Step 2 If you are installing the chassis into an ungrounded rack, you must attach a customer-supplied grounding wire to the
chassis. However, if you are installing the chassis into a grounded rack, you can skip this step.
Step 3 Install the switch onto the 2-post rack:
a. Holding the switch with both hands, position the back of the switch between the two posts of the rack. Then gently
move the switch until the rack-mount brackets come in contact with two rack posts.
b. Holding the chassis level, insert three screws (12-24 or 10-32, depending on the rack type) into each of the two
rack-mount brackets (using a total of six screws) and into the cage nuts or threaded holes in the rack or cabinet posts.
Installing the Cisco MDS 9148T Switch
13
Installing the Cisco MDS 9148T Switch
Installing the Switch into a 2-Post Rack

Figure 7: Installing the Switch onto the 2-Post Rack From the Front Side of the Chassis
Figure 8: Installing the Switch onto the 2-Post Rack From the Rear Side of the Chassis
c. Tighten the 10-32 screws to 20 in-lb (2.26 N.m) or tighten the 12-24 screws to 30 in-lb (3.39 N.m).
Installing the Cisco MDS 9148T Switch
14
Installing the Cisco MDS 9148T Switch
Installing the Switch into a 2-Post Rack

Step 4 If you have attached a grounding wire to the chassis grounding pad, connect the other end of the wire to the facility
ground.
Grounding the Switch
The switch chassis is automatically grounded when you install the switch properly in a grounded rack with
metal-to-metal connections between the switch and rack.
Alternatively, you can ground the chassis (this is required if the rack is not grounded) by attaching a
customer-supplied grounding cable to the chassis grounding pad and the facility ground.
This equipment must be grounded. Never defeat the ground conductor or operate the equipment in the absence
of a suitably installed ground conductor. Contact the appropriate electrical inspection authority or an electrician
if you are uncertain that suitable grounding is available. Statement 1024
Warning
When installing or replacing the unit, the ground connection must always be made first and disconnected last.
Statement 1046
Warning
Step 1 Use a wire-stripping tool to remove approximately 0.75 in. (1.9 cm) of the covering from the end of the grounding wire.
Step 2 Insert the stripped end of the grounding wire into the open end of the grounding lug, and use a crimping tool to crimp
the lug to the wire. Verify that the ground wire is securely attached to the grounding lug by attempting to pull the wire
out of the crimped lug.
Step 3 Remove the label covering the grounding pad on the chassis. Secure the grounding lug to the chassis grounding pad with
two M4 screws, and tighten each screw to 11.5 to 15 in-lb (1.3 to 1.7 N·m) of torque.
Installing the Cisco MDS 9148T Switch
15
Installing the Cisco MDS 9148T Switch
Grounding the Switch

Figure 9: Grounding the Switch
Step 4 Prepare the other end of the grounding wire and connect it to an appropriate grounding point in your site to ensure an
adequate earth ground for the switch. If the rack is fully bonded and grounded, connect the grounding wire, as explained
in the documentation provided by the vendor from whom you bought the rack.
Installing and Removing Components
Hazardous voltage or energy is present on the backplane when the system is operating. Use caution
when servicing. Statement 1034
Warning
During this procedure, wear grounding wrist straps to avoid ESD damage to the switch.
Caution
Installing the ESD Grounding Strap
This section illustrates how to prepare yourself before removing the chassis from the sealed antistatic bag.
The figures show how to cuff the ESD strap around the wrist and the ground cord that connects the cuff to
the ground. ESD wrist straps are the primary means of controlling static charge on personnel.
Installing the Cisco MDS 9148T Switch
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Installing the Cisco MDS 9148T Switch
Installing and Removing Components

These images are for only representation purposes. The chassis' actual appearance and size may vary.
Figure 10: Wearing the ESD Strap
Note
Installing the Cisco MDS 9148T Switch
17
Installing the Cisco MDS 9148T Switch
Installing the ESD Grounding Strap

Figure 11: Handling the Chassis
Installing and Removing Power Supply Units
This section provides instructions for installing and removing the power supply units in the Cisco MDS 9148T
switch.
Installing Power Supply Units
You can replace one power supply unit (PSU) while the other one provides power to the switch.
Before you begin
• To implement n+n redundancy, each PSU must be connected to a separate power feed. Otherwise, only
one power feed is required.
Installing the Cisco MDS 9148T Switch
18
Installing the Cisco MDS 9148T Switch
Installing and Removing Power Supply Units

• There must be an earth ground connection to the chassis to which you are installing the replacement
module. Typically, the chassis is grounded by its metal-to-metal connection with a grounded rack. If you
need to ground the chassis, see Grounding the Switch.
Step 1 Holding the PSU with one hand underneath it and the other hand holding the handle, turn the PSU so that its release latch
is on the right side, and align the back end (the end with the electrical connections) to the open power supply slot. Carefully
slide the PSU all the way into the slot until it clicks into place.
If the PSU does not fit into the slot opening, turn the unit over and try again.
Note
Step 2 Test the installation by trying to pull the PSU out of the slot without using the release latch.
If the PSU does not move out of place, it is secured in the slot. If the PSU moves, carefully press it all the way into the
slot until it clicks in place.
Step 3 Attach the power cable to the electrical outlet on the front of the PSU.
Step 4 Make sure that the other end of the power cable is attached to the appropriate power feed for the PSU. If the power feed
has a switch, slide it to the On position.
Depending on the outlet receptacle on your power distribution unit, you might need the optional jumper
cable to connect the switch to your outlet receptacle.
Note
Step 5 Verify that the PSU is operational by making sure that the PSU LEDs are both green. For information on what the PSU
LEDs indicate, see the LEDs section.
Removing Power Supply Units
You can remove one faulty PSU, while the other one provides enough power to operate the switch.
Step 1 Holding the plug for the power cable, pull the plug out from the power receptacle on the PSU, and wait until both the
PSU LEDs are off.
Step 2 Grasp the PSU handle while pressing the release latch towards the handle.
Step 3 Place your other hand under the PSU to support it while you slide it out of the chassis.
Do not touch the electrical connectors on the back side of the unit and prevent anything else from coming
into contact with and damaging the connectors.
Caution
Installing and Removing Fan Modules
This section provides instructions for installing and removing the fan modules for the Cisco MDS 9148T
switch.
You can replace one of the four fan modules even when the switch is operating so long as you perform the
replacement within one minute of removing the old fan module. If you cannot perform the replacement within
one minute, leave the original fan module in the chassis to maintain the designed airflow until you have the
replacement fan module on hand and can perform the replacement.
Installing the Cisco MDS 9148T Switch
19
Installing the Cisco MDS 9148T Switch
Removing Power Supply Units

If you are replacing a module during operation, be sure that the replacement fan module has the correct
direction of airflow, which means that it has the same airflow direction as the other modules in the chassis.
Also, be sure that the airflow direction takes in air from a cold aisle and sends it out to a hot aisle. Otherwise,
the switch can overheat and shut down.
If you are changing the airflow direction of all the modules in the chassis, you must shut down the switch
before replacing all the fan and power supply modules with modules using the other airflow direction. During
operation, all the modules must have the same direction of airflow.
Caution
Installing a Fan Module
To install a new fan module, follow these steps:
Before you begin
• You must have a new fan module on hand and ready to install within one minute of removing the original
fan module if the switch is operating.
• The new fan module must have the same airflow direction as the other fan and power supply modules
installed in the switch. All of these modules must have either red coloring (port-side intake airflow) or
blue coloring (port-side exhaust airflow).
• Remove any blank plate or existing fan module from the fan slot.
Step 1 Holding the fan module by its handle, align the back of the fan module (the side with the electrical connectors) to the
open fan slot in the chassis.
Step 2 Slide the fan module into the fan module bay until it clicks into place.
Step 3 Verify that the Status LED turns on and becomes green. For more information on what the LEDs indicate, see the LEDs.
Removing a Fan Module
The fan module is designed to be removed and replaced while the system is operating without presenting an
electrical hazard or damaging the system.
The Cisco MDS 9000 Series Switches have internal temperature sensors that can shut down the system if the
temperature within the chassis exceed certain safety thresholds. To accurately monitor the system temperature,
the temperature sensors require sufficient airflow through the chassis. In the event that a fan module is removed
from the chassis and the airflow is reduced, the system will bypass the temperature sensor information and
shut down after five minutes to prevent undetected overheating. However, the switches will shut down sooner
if the major temperature threshold is exceeded.
Caution
While removing the fan module, keep your hands and fingers away from the spinning fan blades. Let
the fan blades completely stop before you remove the fan module. Statement 258
Warning
Installing the Cisco MDS 9148T Switch
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Installing the Cisco MDS 9148T Switch
Installing a Fan Module