Replace Catalyst 3850 Switch - CPS

Introduction

This document describes the steps required to replace a faulty catalyst switch in an Ultra-M setup that hosts StarOS Virtual Network Functions (VNFs).

Background Information

Ultra-M is a pre-packaged and validated virtualized mobile packet core solution designed to simplify the deployment of VNFs. The servers that are part of the Ultra-M setup are connected to three different types of switches:

• Catalyst Switch
• Leaf Switch
• Spine Switch

The network topology of an Ultra-M setup is as shown in this image:

UltraM Network Topology

Note: The Network topology is only a representation, the connections between the switches might slightly vary and it depends on the solution deployed. This document is intended for the Cisco personnel who are familiar with Cisco Ultra-M setup and Catalyst Switch operations.

Abbreviations

Workflow of the MoP

Highlevel Workflow of the Replacement Procedure

Catalyst Switch in an Ultra-M Setup

In an Ultra-M setup, CAT Switch handles these three networks:

• Management Network - Connecting CIMC port of the UCS Servers and Management port of the Nexus Switches
• OpenStack Provisioning Network - Connecting LAN1 port of all the UCS servers
• External network - Connecting to the next hop switch

Every rack in an Ultra-M setup will have one CAT Switch to handle the above three networks for the devices present in the rack. Since there is only one cat switch per rack and there is no redundancy to the CAT switch, during the replacement of a faulty CAT switch the networks handled by the CAT switch will be impacted. But since none of the service level traffic is carried by these networks there would not be any service impact at the time of the replacement procedure.

Prerequisites

1. Take a backup of the configuration file from the CAT switch with the use of ftp/tftp before you proceed with the switch replacement. 

CAT-POD1-01#copy running-config tftp:
Address or name of remote host []? 10.10.10.10 
Destination filename [cat-pod1-01-confg]? running-config-backup

!!
1030 bytes copied in 2.489 secs (395 bytes/sec)

2. Check the current software version running in the switch and make a note of it.

CAT-POD1-01#show version
Cisco IOS Software, IOS-XE Software, Catalyst L3 Switch Software (CAT3K_CAA-UNIVERSALK9-M), Version 03.06.06E RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2016 by Cisco Systems, Inc.
Compiled Sat 17-Dec-16 00:22 by prod_rel_team

<snip> 

Switch Ports Model SW Version SW Image Mode 
------ ----- ----- ---------- ---------- ---- 
* 1 56 WS-C3850-48T 03.06.06E cat3k_caa-universalk9 INSTALL
Configuration register is 0x102

3. Check the current license entitlement.

CAT-POD1-01#show license right-to-use 
 Slot# License name Type Count Period left 
----------------------------------------------------------
 1 ipbase permanent N/A Lifetime

License Level on Reboot: ipbase

4. Make a note of the physical cables connected to the switch and also the port status.

CAT-POD1-01#show int status

Port Name Status Vlan Duplex Speed Type 
Gi1/0/1 Connected to CIMC connected 105 a-full a-1000 10/100/1000BaseTX
Gi1/0/2 Connected to CIMC connected 105 a-full a-1000 10/100/1000BaseTX
Gi1/0/3 Connected to CIMC connected 105 a-full a-1000 10/100/1000BaseTX
Gi1/0/4 Connected to CIMC connected 105 a-full a-1000 10/100/1000BaseTX
Gi1/0/5 Connected to CIMC connected 105 a-full a-1000 10/100/1000BaseTX
Gi1/0/6 Connected to CIMC connected 105 a-full a-1000 10/100/1000BaseTX
Gi1/0/7 Connected to CIMC connected 105 a-full a-1000 10/100/1000BaseTX
Gi1/0/8 Connected to CIMC connected 105 a-full a-1000 10/100/1000BaseTX
Gi1/0/9 Connected to CIMC connected 105 a-full a-1000 10/100/1000BaseTX
Gi1/0/10 notconnect 1 auto auto 10/100/1000BaseTX

<snip>

Switch Replacement Procedure

1. Install the new switch in the rack and connect the cables to the switch as noted. The steps for switch installation can be found in the link below: Catalyst 3850 Switch Hardware Installation Guide

2. Do the Express Setup to enter the initial IP information. This action enables access to the switch through the IP address for further configuration. The steps for performing Express setup can be found in the link below: Catalyst 3850 Switch Getting Started Guide

3. Check the software version of the CAT switch and upgrade/downgrade to the previous software version as per the link given here: Catalyst 3850 Series Switch Upgrade, Management, and Recovery Techniques

4. Check the license level of the new CAT switch and confirm it is as per the old license settings.

CAT-POD1-01#show license right-to-use 
 Slot# License name Type Count Period left 
----------------------------------------------------------
 1 ipbase permanent N/A Lifetime

License Level on Reboot: ipbase

5. Transfer the configuration backup to the new switch.

CAT-POD1-01#copy tftp: running-config
Address or name of remote host []? 10.10.10.10
Source filename []? running-config-backup
Destination filename [running-config]?

Accessing tftp://10.10.10.10/running-config-backup...

Loadingrunning-config-backup from 10.10.10.10 (via FastEthernet0/0): !
[OK - 1030 bytes]

1030 bytes copied in 9.612 secs (107 bytes/sec)

6. Reload the switch after you load the backup configuration.

CAT-POD1-01#reload

7. Once the switch is up, check the port status and confirm it is as before.

CAT-POD1-01#show int status