Cisco WS-C3850-24U-S Catalyst 3850 Switch with 24 Gigabit Ethernet 10/100/1000 Universal Power over Ethernet (UPoE) Ports, 800W PoE Capacity, One 1100W AC Power Supply, Second Slot for optional redundant Power Supply, One Slot for Optional Network Modules, 1 RU Form Factor, Stackable, StackWise-480, StackPower, IP Base Feature Set. 3850 secondary power supply slot I'm having an issue with several switches that were previously deployed with 2 power supplies per switch. I have since re-purposed these switches and I'm only running them with 1 power supply but the switch keeps displaying the amber light and throwing out errors in the logs that the PSU is not responding. Cisco Catalyst 3850 Series- the Industry’s first Fixed, Stackable GE Switch Filed in: Cisco Switches, Hardware, Networking, Reviews, Switch, Technology Tags: 3850 Switch Cisco, C3850-NM-2-10G, C3850-NM-4-10G, C3850-NM-4-1G, Cisco 3850, interface Configuration on NM Modules. Power supply slot B slot is the closest to the outer edge of the switch. Off—Set the power supply off. On—Set the power supply on. By default, the switch power supply is on. The 'power supply switch# slot slot# causes the switch to reload. Each switch in the stack only has a single power supply installed in it. Testing this with a system that has two power supplies installed does not exhibit this issue. Conditions: This issue is reproducible 100% of the time.

• Cisco 3850 Power Supply Slot Booster
• Cisco 3850 Power Supply Slot Box
• Cisco 3850 Power Supply Slot Block
• Cisco 3850 Power Supply Slot Bracket

It is sometimes confusing on which interfaces are available and which can be configured when using one of the NM modules in a Cisco 3850 Switch. We currently offer three different modules:

C3850-NM-4-1G (four 1-Gigabit SFP module slots)

C3850-NM-2-10G (Combination of 1-Gig and 10-Gig ports)

C3850-NM-4-10G (four 10-Gigabit slots or four 1-Gigabit slots)

The available configuration is based on which model NM you are using. The intent of this document is to help clear up some of the misunderstood configuration options. Below are details on each NM module and how to configure each one when inserted into the switch.

C3850-NM-4-1G:

This module has four 1-Gigabit SFP module slots. Any combination of standard SFP modules are supported. SFP+ modules are not supported. If you insert an SFP+ module in the 1-Gigabit network module, the SFP+ module does not operate, and the switch logs an error message.

C3850-NM-2-10G:

This module has four slots that support the following combinations:

• Two slots (left side) support only 1-Gigabit SFP modules and two slots (right side) support either 1-Gigabit SFP or 10-Gigabit SFP modules.

• Three slots (left side) support 1-Gigabit SFP modules and one slot (right side) supports 10-Gigabit Ethernet SFP+.

Supported combinations of SFP and SFP+ modules:

• Slots 1, 2, 3, and 4 populated with 1-Gigabit SFP modules.

• Slots 1 and 2 populated with 1-Gigabit SFP modules, and Slot 4 populated with one 10-Gigabit SFP+ module.

• Slot 3 and Slot 4 each populated with 10-Gigabit SFP+ modules.

C3850-NM-4-10G:

This module has four 10-Gigabit slots or four 1-Gigabit slots.

Cisco 3850 Power Supply Slot Booster

Note: This is only supported on the 48-port models.

Configuration:

For the C3850-NM-4-1G module – All ports are natively Gig and are configured as Gig1/1/1 through Gig1/1/4

<snippet>

interface GigabitEthernet1/1/1 <——– Config this interface
!
interface GigabitEthernet1/1/2 <——– Config this interface
!
interface GigabitEthernet1/1/3 <——– Config this interface
!
interface GigabitEthernet1/1/4 <——– Config this interface
!
interface TenGigabitEthernet1/1/1 <——– Disregard
!
interface TenGigabitEthernet1/1/2 <——– Disregard
!
interface TenGigabitEthernet1/1/3 <——– Disregard
!
interface TenGigabitEthernet1/1/4 <——– Disregard

Cisco 3850 Power Supply Slot Box

For the C3850-NM-4-10G module – All ports default to 10G and should be configured as
TenGig1/1/1 through TenGig1/1/4 – even though you are operating them as 1G via SFPs.

<snippet>

interface GigabitEthernet1/1/1 <——– Disregard
!
interface GigabitEthernet1/1/2 <——– Disregard
!
interface GigabitEthernet1/1/3 <——– Disregard
!
interface GigabitEthernet1/1/4 <——– Disregard
!
interface TenGigabitEthernet1/1/1 <——– Config this interface
!
interface TenGigabitEthernet1/1/2 <——– Config this interface
!
interface TenGigabitEthernet1/1/3 <——– Config this interface
!
interface TenGigabitEthernet1/1/4 <——– Config this interface

For the C3850-NM-2-10G module – The first two ports are natively 1G ports and the last two ports are natively 10G ports. So you configure the 1Gig ports as Gig1/1/1 through Gig1/1/2, and configure the last two ports as TenGig1/1/3 through TenGig1/1/4 – even if you are operating the last two ports as 1G.

## This is commonly misunderstood ##

<snippet>

interface GigabitEthernet1/1/1 <——– Config this interface
!
interface GigabitEthernet1/1/2 <——– Config this interface
!
interface GigabitEthernet1/1/3 <——– Disregard
!
interface GigabitEthernet1/1/4 <——– Disregard
!
interface TenGigabitEthernet1/1/1 <——– Disregard
!
interface TenGigabitEthernet1/1/2 <——– Disregard
!
interface TenGigabitEthernet1/1/3 <——– Config this interface even if using 1G
!
interface TenGigabitEthernet1/1/4 <——– Config this interface even if using 1G

Cisco 3850 Power Supply Slot Block

** There are only 4 interfaces which are valid and the other 4 should not be used even though they still show up in the CLI

Supported GBICs:

TenGig

• SFP-H10GB-CU1M
• SFP-H10GB-CU3M
• SFP-H10GB-CU5M
• SFP-10G-SR
• SFP-10G-LRM
• SFP-10G-LR
• SFP-10G-ER

OneGig

Cisco 3850 Power Supply Slot Bracket

• GLC-T (10/100/1000)
• GLC-SX-MM
• GLC-LH-SM
• GLC-SX-MMD
• GLC-LH-SMD
• GLC-ZX-SM
• GLC-ZX-SMD
• GLC-BX-D
• GLC-BX-U
• CWDM SFP
• SFP-GE-S
• SFP-GE-L
• SFP-GE-Z
• DWDM SFP
• DWDM SFP (add.)

Reference:

Installing a Network Module

10-Gigabit Ethernet Transceiver Modules Compatibility Matrix

Cisco Gigabit Ethernet Transceiver Modules Compatibility Matrix

Original Doc you can refer to: https://supportforums.cisco.com/docs/DOC-36084

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