Cisco Catalyst 3850 Manual

Switch Installation
For initial switch setup, assigning the switch IP address, and powering on information, see the switch getting
started guide on Cisco.com.
This chapter contains these topics:
•Preparing for Installation, page 1
•Planning a Switch Data Stack, page 4
•Data Stack Cabling Configurations, page 6
•Planning a StackPower Stack, page 9
•StackPower Cabling Configurations, page 10
•Installing the Switch, page 12
•Connecting to the StackWise Ports, page 16
•Connecting to the StackPower Ports, page 18
•Installing a Network Module in the Switch, page 18
•Installing and Removing SFP, SFP+ and QSFP+ Modules, page 19
•Connecting Devices to the Ethernet Ports, page 19
•Where to Go Next, page 21
Preparing for Installation
Safety Warnings
This section includes the basic installation caution and warning statements. Read this section before you start
the installation procedure. Translations of the warning statements appear in the Catalyst 3850 switch RCSI
guide on Cisco.com.
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Before working on equipment that is connected to power lines, remove jewelry (including rings, necklaces,
and watches). Metal objects will heat up when connected to power and ground and can cause serious burns
or weld the metal object to the terminals. Statement 43
Warning
Do not stack the chassis on any other equipment. If the chassis falls, it can cause severe bodily injury and
equipment damage. Statement 48
Warning
Ethernet cables must be shielded when used in a central office environment. Statement 171Warning
Do not work on the system or connect or disconnect cables during periods of lightning activity. Statement
1001
Warning
Read the installation instructions before connecting the system to the power source. Statement 1004Warning
Class 1 laser product. Statement 1008Warning
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
The plug-socket combination must be accessible at all times, because it serves as the main disconnecting
device. Statement 1019
Warning
Use copper conductors only. Statement 1025Warning
This unit might have more than one power supply connection. All connections must be removed to
de-energize the unit. Statement 1028
Warning
Only trained and qualified personnel should be allowed to install, replace, or service this equipment.
Statement 1030
Warning
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Safety Warnings

Ultimate disposal of this product should be handled according to all national laws and regulations. Statement
1040
Warning
To prevent the system from overheating, do not operate it in an area that exceeds the maximum
recommended ambient temperature of: <113°F (45°C). Statement 1047
Warning
Installation of the equipment must comply with local and national electrical codes. Statement 1074Warning
To prevent airflow restriction, allow clearance around the ventilation openings to be at least: 3 inches (7.6
cm). Statement 1076
Warning
The grounding architecture of this product is DC-isolated (DC-I).Note
Installation Guidelines
When determining where to install the switch, verify that these guidelines are met:
•Clearance to the switch front and rear panel meets these conditions:
◦Front-panel LEDs can be easily read.
◦Access to ports is sufficient for unrestricted cabling.
◦AC power cord can reach from the AC power outlet to the connector on the switch rear panel.
◦The SFP or SFP+ module minimum bend radius and connector length is met. See the SFP or SFP+
module documentation for more information.
•Cabling is away from sources of electrical noise, such as radios, power lines, and fluorescent lighting
fixtures. Make sure that the cabling is safely away from other devices that might damage the cables.
•For switches with the optional 1100-W power-supply module (PWR-C1-1100WAC=), first rack-mount
the switch before installing the power-supply module.
•Make sure power-supply modules and fan modules are securely inserted in the chassis before moving
the switch.
•When connecting or disconnecting the power cord on a switch that is installed above or below a 1100-W
power supply-equipped switch, you might need to remove the module from the switch to access the
power cord.
•Airflow around the switch and through the vents is unrestricted.
•For copper connections on Ethernet ports, cable lengths from the switch to connected devices can be up
to 328 feet (100 meters).
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Switch Installation
Installation Guidelines

•Temperature around the unit does not exceed 113°F (45°C). If the switch is installed in a closed or
multirack assembly, the temperature around it might be greater than normal room temperature.
•Humidity around the switch does not exceed 95 percent.
•Altitude at the installation site is not greater than 10,000 feet.
•Cooling mechanisms, such as fans and blowers in the switch, can draw dust and other particles causing
contaminant buildup inside the chassis, which can result in system malfunction. You must install this
equipment in an environment as free from dust and foreign conductive material (such as metal flakes
from construction activities) as is possible.
Box Contents
The switch getting started guide describes the box contents. If any item is missing or damaged, contact your
Cisco representative or reseller for support.
Tools and Equipment
Obtain these necessary tools and equipment:
•A number-2 Phillips screwdriver to rack-mount the switch.
Verifying Switch Operation
Before you install the switch in a rack, or on a table or shelf, you should power on the switch and verify that
the switch passes POST. See the “Running Express Setup”section in the getting started guide for the steps
required to connect a PC to the switch and to run Express Setup.
Powering Off the Switch
After a successful POST, disconnect the power cord from the switch. Install the switch in a rack, on a table,
or on a shelf as described in Installing the Switch, on page 12.
Planning a Switch Data Stack
Catalyst 3850 switches can share bandwidth by using data stacking.
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Box Contents

The following switch models do not support StackWise-480:Note
•WS-C3850-48XS-S
•WS-C3850-48XS-E
•WS-C3850-48XS-F-S
•WS-C3850-48XS-F-E
Switch Stacking and Power Stacking Guidelines
Before connecting the switches in a stack, keep in mind these stacking guidelines:
•Size of the switch and any optional power-supply module. The 1100-W power-supply module is longer
than the other modules. Stacking switches with the same power-supply modules together makes it easier
to cable the switches.
•Length of cable. Depending on the configurations that you have, you might need different-sized cables.
If you do not specify the length of the StackWise cable, the 0.5-meter cable is supplied. If you need the
1-meter cable or the 3-meter cable, you can order it from your Cisco supplier. For cable part numbers,
see StackWise Ports. The Data Stack Cabling Configurations, on page 6 provides examples of
recommended configurations.
•For rack-mounted switch stacks that are members of a StackPower stack as well as a data stack, see
Planning a StackPower Stack, on page 9.
•You can create data stacks with up to nine switches in a stack.
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Switch Installation
Switch Stacking and Power Stacking Guidelines

Special considerations for the following switch models:Note
•WS-C385-24XS-E
•WS-C385-24XS-S
•WS-C385-24XU-E
•WS-C385-24XU-L
•WS-C385-24XU-S
•WS-C3850-12X48U-L
•WS-C3850-12X48U-S
•WS-C3850-12X48U-E
Information:
•If you set up a stack with these switches, the stack can have a maximum of 8 switches only. Each
of the above switch models have 4 ASIC chips, and the maximum number of ASIC chips per stack
cannot exceed 32.
•If you set up a stack that contains the above switches and other Catalyst 3850 switches, ensure that
the maximum number of ASIC chips is 32.
The Catalyst WS-C3850-48XS switch models do not support power stacking.Note
Data Stack Cabling Configurations
This is an example of a recommended configuration that uses the supplied 0.5-meter StackWise cable. In this
example, the switches are stacked in a vertical rack or on a table. This configuration provides redundant
connections. The configuration example uses the supplied 0.5-meter StackWise cable. The example shows
the full-ring configuration that provides redundant connections.
Figure 1: Data Stacking the Catalyst 3850 Switches in a Rack or on a Table Using the 0.5-meter StackWise Cables
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Data Stack Cabling Configurations

This example shows a recommended configuration when the switches are mounted side-by-side. Use the
1-meter and the 3-meter StackWise cables to connect the switches. This configuration provides redundant
connections.
Figure 2: Data Stacking in a Side-by-Side Mounting
Data Stack Bandwidth and Partitioning Examples
This section provides examples of data stack bandwidth and possible data stack partitioning. The figure shows
a data stack of Catalyst 3850 switches that provides full bandwidth and redundant StackWise cable connections.
Figure 3: Example of a Data Stack with Full Bandwidth Connections
This figure shows an example of a stack of Catalyst 3850 switches with incomplete StackWise cabling
connections. This stack provides only half bandwidth and does not have redundant connections.
Figure 4: Example of a Data Stack with Half Bandwidth Connections
The figures below show data stacks of Catalyst 3850 switches with failover conditions. In this figure, the
StackWise cable is bad in link 2. Therefore, this stack provides only half bandwidth and does not have redundant
connections.
Figure 5: Example of a Data Stack with a Failover Condition
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Switch Installation
Data Stack Bandwidth and Partitioning Examples

In this figure, link 2 is bad. Therefore, this stack partitions into two stacks, and the top and bottom switches
become the active switch in the stack. If the bottom switch is a member (not active or standby switch), it
reloads.
Figure 6: Example of a Partitioned Data Stack with a Failover Condition
Power-On Sequence for Switch Stacks
Consider these guidelines before you power on the switches in a stack:
•The sequence in which the switches are first powered on might affect the switch that becomes the stack
master.
•There are two ways to elect an active switch:
•If you want a particular switch to become the active switch, configure it with the highest priority.
Among switches with same priority, the switch with the lowest MAC address becomes the active
switch.
•If you want a particular switch to become the active switch, power on that switch first. This switch
remains the active switch until a reelection is required. After 2 minutes, power on the other switches
in the stack. If you have no preference as to which switch becomes the active switch, power on all
the switches in the stack within 1 minute. These switches participate in the active switch election.
Switches powered on after 2 minutes do not participate in the election.
If changes are made to the stack without powering down the switches, the following results can occur:
•If two operating partial ring stacks are connected together using a stack cable, a stack merge can take
place. This situation reloads the whole stack (all switches in the stack).
•If some switches in the stack are completely separated from the stack, a stack split can occur.
•A stack split can occur on a full ring stack if:
◦More than one running switch is removed without powering down.
◦More than one stack cable is removed without powering down.
•A stack split can occur in a partial ring stack if:
◦A switch is removed without powering down.
◦A stack cable is removed without powering down.
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Power-On Sequence for Switch Stacks

•In a split stack, depending on where the active and standby switches are located, either two stacks might
be formed (with the standby taking over as the new active switch in the newly formed stack) or all the
members in the newly formed stack might reload.
These results depend on how the switches are connected. You can remove two or more switches from the
stack without splitting the stack.
Note
For conditions that can cause a stack reelection or to manually elect the active switch, see the stacking software
configuration guide on Cisco.com at this URL: .
Planning a StackPower Stack
StackPower Stacking Guidelines
You can configure a StackPower stack for either power sharing or redundancy. In power-sharing mode, the
power of all the power supplies in the stack is aggregated and distributed among the stack members.
In redundant mode, when the total power budget of the stack is calculated, the wattage of the largest power
supply is not included. That power is held in reserve and used to maintain power to switches and attached
devices when one power supply fails. Following the failure of a power supply, the StackPower mode becomes
power sharing.
Power-sharing mode is the recommended configuration for Catalyst 3850 switches.Note
For general concepts and management procedures for switch power stacks, see the software stacking
configuration guide on Cisco.com.
Before connecting the switches in a power stack, keep in mind these guidelines:
•A switch power stack can include a maximum of four switches in a ring topology and nine switches in
a star topology.
•Size of the switch and any optional power supply module. The 1100-W power-supply module is 1.5
inches (3.81 cm) longer than the other modules, and with the attached cable retention clip, it extends 3
inches (7.62 cm) from the switch chassis. Stacking switches with the same power-supply modules
together makes it easier to cable the switches. For switch dimensions, see Appendix A, “Technical
Specifications.”
•Length of cable. Depending on the configurations that you have, you might need different-sized cables.
If you do not specify the length of the StackPower cable, the 0.3 meter cable is supplied. If you need
the 1.5 meter cable, you can order it from your Cisco supplier. For cable part numbers, see StackPower
Connector. The StackPower Cabling Configurations, on page 10 provides examples of recommended
configurations.
•For rack-mounted switch stacks that are members of a data stack and a StackPower stack, see Switch
Stacking and Power Stacking Guidelines, on page 5.
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Switch Installation
Planning a StackPower Stack

StackPower Cabling Configurations
This section describes the recommended cabling configurations for a StackPower stack. There are two types
of StackPower cables.
The cable in the figure connects a Catalyst 3850 switch to another Catalyst 3850 switch in a power stack or
with an XPS. StackPower cables have color bands on the cable ends:
•The cable end with the green band can connect only to a Catalyst 3850 switch.
•The cable end with the yellow band can connect to a Catalyst 3850 switch or an XPS.
The cable is available in two lengths.
LengthCable TypePart Number
0.3 meterStackPower CableCAB-SPWR-30CM
1.5 meterStackPower CableCAB-SPWR-150CM
Figure 7: StackPower Cable for Use with Catalyst 3850 Switches
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Switch Installation
StackPower Cabling Configurations

This figure shows a ring configuration using both of the supplied 0.3-meter StackPower cables and one
1.5-meter cable. In the examples that follow, the switches are stacked in a vertical rack or on a table.
Figure 8: StackPower Ring Topology
This figure shows nine switches connected in a star topology.
Figure 9: StackPower Star Topology
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Switch Installation
StackPower Cabling Configurations

StackPower Partitioning Examples
These figures show StackPower stacks of Catalyst 3850 switches with failover conditions.
In this figure, the StackPower cable 2 is faulty. Therefore, this stack does not provide redundancy.
Figure 10: Example of a StackPower Stack with a Failover Condition
In this figure, StackPower port B on the center switch has failed and this stack partitions into two stacks. The
top two switches share power, and the bottom switch is now a separate stack.
Figure 11: Example of a Partitioned StackPower Stack with a Failover Condition
Installing the Switch
Rack-Mounting
Installation in racks other than 19-inch racks requires a bracket kit not included with the switch.
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Switch Installation
StackPower Partitioning Examples

To prevent bodily injury when mounting or servicing this unit in a rack, you must take special precautions
to ensure that the system remains stable. The following guidelines are provided to ensure your safety:
Warning
•This unit should be mounted at the bottom of the rack if it is the only unit in the rack.
•When mounting this unit in a partially filled rack, load the rack from the bottom to the top with the
heaviest component at the bottom of the rack.
•If the rack is provided with stabilizing devices, install the stabilizers before mounting or servicing
the unit in the rack.
Statement 1006
This figure shows the standard 19-inch brackets and other optional mounting brackets. You can order the
optional brackets from your Cisco sales representative.
Figure 12: Rack-Mounting Brackets
23-inch brackets (C3850-RACK-KIT=)419-inch brackets (C3850-RACK-KIT=)1
24-inch brackets (C3850-RACK-KIT=)5Extension rails and brackets for four-point
mounting, includes 19-inch brackets.
(C3850-4PT-KIT=)
2
ETSI brackets (C3850-RACK-KIT=)3
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Switch Installation
Rack-Mounting

Attaching the Rack-Mount Brackets
Procedure
Use four Phillips flat-head screws to attach the long side of the bracket to each side of the switch for the front-
or rear-mounting positions.
Figure 13: Attaching Brackets for 19-inch Racks
Front-mounting position3Rear-mounting position1
Number-8 Phillips flat-head screws2
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Switch Installation
Rack-Mounting

Figure 14: Attaching Brackets for Catalyst WS-C3850-48XS Switches
Mounting the Switch a Rack
Procedure
Step 1 Use the four supplied Phillips machine screws to attach the brackets to the rack.
Step 2 Use the black Phillips machine screw to attach the cable guide to the left or right bracket.
Front-mounting position4Phillips machine screw, black1
Number-12 or number-10 Phillips machine
screws
5Cable guide2
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Switch Installation
Rack-Mounting

Installing the Switch on a Table or Shelf
Procedure
Step 1 To install the switch on a table or shelf, locate the adhesive strip with the rubber feet in the mounting-kit
envelope.
Step 2 Attach the four rubber feet to the four circular etches on the bottom of the chassis.
Step 3 Place the switch on the table or shelf near an AC power source.
Step 4 When you complete the switch installation, see After Switch Installation, on page 16 for information on
switch configuration.
After Switch Installation
•Configure the switch by running Express Setup to enter the initial switch configuration. See the switch
getting started guide on Cisco.com.
•Use the CLI setup program to enter the initial switch configuration.
•Connect to the stack ports.
•Connect to the front-panel ports.
Connecting to the StackWise Ports
Before You Begin
Before connecting the StackWise cables, review the Planning a Switch Data Stack, on page 4. Always use
a Cisco-approved StackWise cable to connect the switches.
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Switch Installation
Installing the Switch on a Table or Shelf

Procedure
Step 1 Remove the dust covers from the StackWise cables and StackWise ports, and store them for future use.
Step 2 Connect the cable to the StackWise port on the switch rear panel. Align the connector and connect the StackWise
cable to the StackWise port on the switch rear panel and finger-tighten the screws (clockwise direction). Make
sure the Cisco logo is on the top side of the connector as shown in the figure.
Step 3 Connect the other end of the cable to the port on the other switch and finger-tighten the screws. Avoid
overtightening the screws.
Figure 15: Connecting the StackWise Cable in a StackWise Port
Connector screw3Cisco logo1
Connector screw2
Removing and installing the StackWise cable can shorten its useful life. Do not remove and insert
the cable more often than is absolutely necessary (installing and removing it up to 200 times is
supported).
Caution
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Switch Installation
Connecting to the StackWise Ports

When you need to remove the StackWise cable from the connector, make sure to fully unscrew the correct
screws. When the connectors are not being used, replace the dust covers.
Connecting to the StackPower Ports
Before You Begin
Before connecting the StackPower cables, review Planning a Switch Data Stack, on page 4. Always use a
Cisco-approved StackWise cable to connect the switches. To prevent misconfiguration, the StackPower ports
on the switch are keyed and have colored bands that match the keying and bands on the StackPower cable
connectors.
Procedure
Step 1 Remove the dust covers from the StackPower cable connectors.
Step 2 Connect the end of the cable with a green band to either StackPower port on the first switch. Align the connector
correctly, and insert it into a StackPower port on the switch rear panel.
Step 3 Connect the end of the cable with the yellow band to another Catalyst 3850 switch (to configure StackPower
power sharing).
Step 4 Hand-tighten the captive screws to secure the StackPower cable connectors in place.
Figure 16: Connecting the StackPower Cable to a StackPower Port
Removing and installing the StackPower cable can shorten its useful life. Do not remove and insert
the cable more often than is absolutely necessary.
Caution
Installing a Network Module in the Switch
See these sections for information on network modules:
•Installing Network Modules
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Switch Installation
Connecting to the StackPower Ports

Installing and Removing SFP, SFP+ and QSFP+ Modules
See these sections for information on SFP, SFP+ and QSFP+ modules:
•Installing SFP and SFP+ Modules
•Removing SFP and SFP+ Modules
•Cisco 40-Gigabit QSFP+ Transceiver Modules Installation Note
Connecting Devices to the Ethernet Ports
•10/100/1000 Port Connections, on page 19
•PoE+ and Cisco UPOE Port Connections, on page 20
10/100/1000 Port Connections
The switch 10/100/1000 port configuration changes to operate at the speed of the attached device. If the
attached ports do not support autonegotiation, you can manually set the speed and duplex parameters.
Connecting devices that do not autonegotiate or that have the speed and duplex parameters manually set can
reduce performance or result in no linkage.
To maximize performance, choose one of these methods for configuring the Ethernet ports:
•Let the ports autonegotiate both speed and duplex.
•Set the interface speed and duplex parameters on both ends of the connection.
Be careful when connecting a “snagless”Ethernet cable to port 1 on a 48-port switch. The protective boot
of the cable might inadvertently press the Mode button, which could cause the switch to erase its startup
configuration and reboot. See this field notice for more information: http://www.cisco.com/c/en/us/support/
docs/field-notices/636/fn63697.html
This issue does not occur if you are using Cisco IOS XE Release 3E or later releases.
Note
Auto-MDIX Connections
The autonegotiation and the auto-MDIX features are enabled by default on the switch.
With autonegotiation, the switch port configurations change to operate at the speed of the attached device. If
the attached device does not support autonegotiation, you can manually set the switch interface speed and
duplex parameters.
With auto-MDIX, the switch detects the required cable type for copper Ethernet connections and configures
the interface accordingly.
If auto-MDIX is disabled, use the guidelines in this table to select the correct cable.
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Switch Installation
Installing and Removing SFP, SFP+ and QSFP+ Modules

Table 1: Recommended Ethernet Cables (When Auto-MDIX is Disabled)
Straight-Through CableCrossover Cable1 Device
NoYesSwitch to switch
NoYesSwitch to hub
YesNoSwitch to computer or server
YesNoSwitch to router
YesNoSwitch to IP phone
1100BASE-TX and 1000BASE-T traffic requires twisted four-pair, Category 5, Category 5e, or Category 6 cable. 10BASE-T traffic can use Category 3 or
Category 4 cable.
PoE+ and Cisco UPOE Port Connections
The 10/100/1000 PoE+ and Cisco UPOE ports have the same autonegotiation settings and cabling requirements
that are described in the 10/100/1000 Port Connections, on page 19. These ports can provide PoE, PoE+, or
Cisco UPOE inline power.
Be careful when connecting a “snagless”Ethernet cable to port 1 on a 48-port switch. The protective boot
of the cable might inadvertently press the Mode button, which might cause the switch to erase its startup
configuration and reboot. See this field notice for more information: http://www.cisco.com/c/en/us/support/
docs/field-notices/636/fn63697.html
This issue does not occur if you are using Cisco IOS XE Release 3E or later releases.
Note
PoE inline power supports devices compliant with the IEEE 802.3af standard, as well as prestandard Cisco
IP Phones and Cisco Aironet Access Points. Each port can deliver up to 15.4 W of PoE. PoE+ inline power
supports devices compliant with the IEEE 802.3at standard, by delivering up to 30 W of PoE+ power per port
to all switch ports.
See Power Supply Modules for the power supply modules required to support PoE, PoE+, and Cisco UPOE
on 24- and 48-port switches.
Voltages that present a shock hazard may exist on Power over Ethernet (PoE) circuits if interconnections
are made using uninsulated exposed metal contacts, conductors, or terminals. Avoid using such
interconnection methods, unless the exposed metal parts are located within a restricted access location
and users and service people who are authorized within the restricted access location are made aware of
the hazard. A restricted access area can be accessed only through the use of a special tool, lock and key
or other means of security. Statement 1072
Warning
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PoE+ and Cisco UPOE Port Connections