Replacement of Catalyst 3850 Switch - vEPC

Introduction

This document describes the steps required in order to replace a faulty Catalyst (CAT) 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 that is designed in order to simplify the deployment of VNFs. The servers that are part of the Ultra-M setup are connected to three different types of switches:

• CAT Switch
• Leaf Switch
• Spine Switch

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

UltraM Network Topology

Note: The Network topology is only a representation. The connections between the switches might slightly vary and that depends on the solution deployed.

This document is intended for Cisco personnel who are familiar with Cisco Ultra-M setup and CAT Switch operations.

Abbreviations

VNF	Virtual Network Function
MOP	Method of Procedure
LAN	Local Area Network
FTP	File Transfer Protocol
TFTP	Trivial File Transfer Protocol
CIMC	Cisco Integrated Management Controller

Workflow of the MoP

Highlevel Workflow of the Replacement Procedure

CAT Switch in an Ultra-M Setup

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

Managment Network - Connects CIMC port of the UCS Servers and Management port of the Nexus Switches.

OpenStack Provisioning Network - Connects LAN1 port of all the UCS servers.

External network - Connects to the next hop switch.

Every rack in an Ultra-M setup has one CAT Switch in order to handle these 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, at the time of the replacement of a faulty CAT Switch, the networks handled by the CAT Switch will be impacted. However, 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

Take a backup of the configuration file from the CAT Switch with the use of the 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)

Check the current software version that runs 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

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

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

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

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 in order to perform Express setup can be found in this link: Catalyst 3850 Switch Getting Started Guide.

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.

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

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)

Reload the switch after you load the backup configuration:

CAT-POD1-01#reload

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

CAT-POD1-01#show int status