Cisco Nexus 3500 Series NX-OS Software Upgrade and Downgrade Guide, Release 7.x

Transcription

1 Cisco Nexus 3500 Series NX-OS Software Upgrade and Downgrade Guide, Release 7.x First Published: Americas Headquarters Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA USA Tel: NETS (6387) Fax:

2 THE SPECIFICATIONS AND INFORMATION REGARDING THE PRODUCTS IN THIS MANUAL ARE SUBJECT TO CHANGE WITHOUT NOTICE. ALL STATEMENTS, INFORMATION, AND RECOMMENDATIONS IN THIS MANUAL ARE BELIEVED TO BE ACCURATE BUT ARE PRESENTED WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED. USERS MUST TAKE FULL RESPONSIBILITY FOR THEIR APPLICATION OF ANY PRODUCTS. THE SOFTWARE LICENSE AND LIMITED WARRANTY FOR THE ACCOMPANYING PRODUCT ARE SET FORTH IN THE INFORMATION PACKET THAT SHIPPED WITH THE PRODUCT AND ARE INCORPORATED HEREIN BY THIS REFERENCE. IF YOU ARE UNABLE TO LOCATE THE SOFTWARE LICENSE OR LIMITED WARRANTY, CONTACT YOUR CISCO REPRESENTATIVE FOR A COPY. The Cisco implementation of TCP header compression is an adaptation of a program developed by the University of California, Berkeley (UCB) as part of UCB's public domain version of the UNIX operating system. All rights reserved. Copyright 1981, Regents of the University of California. NOTWITHSTANDING ANY OTHER WARRANTY HEREIN, ALL DOCUMENT FILES AND SOFTWARE OF THESE SUPPLIERS ARE PROVIDED AS IS" WITH ALL FAULTS. CISCO AND THE ABOVE-NAMED SUPPLIERS DISCLAIM ALL WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, THOSE OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OR ARISING FROM A COURSE OF DEALING, USAGE, OR TRADE PRACTICE. IN NO EVENT SHALL CISCO OR ITS SUPPLIERS BE LIABLE FOR ANY INDIRECT, SPECIAL, CONSEQUENTIAL, OR INCIDENTAL DAMAGES, INCLUDING, WITHOUT LIMITATION, LOST PROFITS OR LOSS OR DAMAGE TO DATA ARISING OUT OF THE USE OR INABILITY TO USE THIS MANUAL, EVEN IF CISCO OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental. This product includes cryptographic software written by Eric Young (eay@cryptsoft.com). This product includes software developed by the OpenSSL Project for use in the OpenSSL Toolkit. ( This product includes software written by Tim Hudson (tjh@cryptsoft.com). Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S. and other countries. To view a list of Cisco trademarks, go to this URL: Third-party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (1110R) 2018 Cisco Systems, Inc. All rights reserved.

3 CONTENTS PREFACE Preface v Audience v Document Conventions v Obtaining Documentation and Submitting a Service Request vi Documentation Feedback vi Related Documentation for Cisco Nexus 3000 Series Switches vi CHAPTER 1 New and Changed Information 1 New and Changed Information 1 CHAPTER 2 Upgrading or Downgrading the Cisco Nexus 3500 Series NX-OS Software 3 About the Software Image 3 Prerequisites for Upgrading the Cisco NX-OS Software 3 Prerequisites for Downgrading the Cisco NX-OS Software 4 Cisco NX-OS Software Upgrade Guidelines 4 Cisco NX-OS Software Downgrade Guidelines 5 Booting the Switch from the USB 5 Upgrading the Cisco NX-OS Software 6 Downgrading to an Earlier Software Release 10 iii

4 Contents iv

5 Preface This preface includes the following sections: Audience, on page v Document Conventions, on page v Obtaining Documentation and Submitting a Service Request, on page vi Documentation Feedback, on page vi Related Documentation for Cisco Nexus 3000 Series Switches, on page vi Audience This publication is for network administrators who install, configure, and maintain Cisco Nexus switches. Document Conventions Command descriptions use the following conventions: Convention Description bold Bold text indicates the commands and keywords that you enter literally as shown. Italic Italic text indicates arguments for which the user supplies the values. [x] Square brackets enclose an optional element (keyword or argument). [x y] Square brackets enclosing keywords or arguments separated by a vertical bar indicate an optional choice. {x y} Braces enclosing keywords or arguments separated by a vertical bar indicate a required choice. [x {y z}] Nested set of square brackets or braces indicate optional or required choices within optional or required elements. Braces and a vertical bar within square brackets indicate a required choice within an optional element. v

6 Obtaining Documentation and Submitting a Service Request Preface Convention variable string Description Indicates a variable for which you supply values, in context where italics cannot be used. A nonquoted set of characters. Do not use quotation marks around the string or the string will include the quotation marks. Examples use the following conventions: Convention screen font boldface screen font italic screen font < > [ ]!, # Description Terminal sessions and information the switch displays are in screen font. Information you must enter is in boldface screen font. Arguments for which you supply values are in italic screen font. Nonprinting characters, such as passwords, are in angle brackets. Default responses to system prompts are in square brackets. An exclamation point (!) or a pound sign (#) at the beginning of a line of code indicates a comment line. Obtaining Documentation and Submitting a Service Request For information on obtaining documentation, using the Cisco Bug Search Tool (BST), submitting a service request, and gathering additional information, see What's New in Cisco Product Documentation at: Subscribe to What's New in Cisco Product Documentation, which lists all new and revised Cisco technical documentation as an RSS feed and delivers content directly to your desktop using a reader application. The RSS feeds are a free service. Documentation Feedback To provide technical feedback on this document, or to report an error or omission, please send your comments to nexus3k-docfeedback@cisco.com. We appreciate your feedback. Related Documentation for Cisco Nexus 3000 Series Switches The entire Cisco Nexus 3000 Series switch documentation set is available at the following URL: tsd-products-support-series-home.html vi

7 CHAPTER 1 New and Changed Information This chapter provides release-specific information for each new and changed feature in the Cisco Nexus 3500 Series NX-OS Software Upgrade and Downgrade Guide, Release 7.x. New and Changed Information, on page 1 New and Changed Information This table summarizes the new and changed features for the Cisco Nexus 3500 Series NX-OS Software Upgrade and Downgrade Guide, Release 7.x and tells you where they are documented. Table 1: New and Changed Features for Cisco NX-OS Release 7.x Feature Description Changed Where Documented in Release Software upgrade Added the support to upgrade from Cisco NX-OS Release 6.0(2)A8(x) to Cisco NX-OS Release 7.0(3)I7(2). 7.0(3)I7(2) Upgrading the Cisco NX-OS Software, on page 6 1

8 New and Changed Information New and Changed Information 2

9 CHAPTER 2 Upgrading or Downgrading the Cisco Nexus 3500 Series NX-OS Software This chapter describes how to upgrade or downgrade the Cisco NX-OS software. It contains the following sections: About the Software Image, on page 3 Prerequisites for Upgrading the Cisco NX-OS Software, on page 3 Prerequisites for Downgrading the Cisco NX-OS Software, on page 4 Cisco NX-OS Software Upgrade Guidelines, on page 4 Cisco NX-OS Software Downgrade Guidelines, on page 5 Booting the Switch from the USB, on page 5 Upgrading the Cisco NX-OS Software, on page 6 Downgrading to an Earlier Software Release, on page 10 About the Software Image Each device is shipped with the Cisco NX-OS software. The Cisco NX-OS software consists of two NXOS software images, kickstart image and systems image (for example: n3500-uk9-kickstart a6.7.bin and n3500-uk a6.7.bin). Only these images are required to load the Cisco NX-OS operating system. These images run on all Cisco Nexus 3500 Series switches. Note Another type of binary file is the software maintenance upgrade (SMU) package file. SMUs contain fixes for specific defects. They are created to respond to immediate issues and do not include new features. SMU package files are available for download from Cisco.com and generally include the ID number of the resolved defect in the filename. For more information on SMUs, see the Cisco Nexus 3500 Series NX-OS System Management Configuration Guide. Prerequisites for Upgrading the Cisco NX-OS Software Upgrading the Cisco NX-OS software has the following prerequisites: 3

10 Prerequisites for Downgrading the Cisco NX-OS Software Upgrading or Downgrading the Cisco Nexus 3500 Series NX-OS Software Ensure that everyone who has access to the device or the network is not configuring the device or the network during this time. You cannot configure a device during an upgrade. Use the show configuration session summary command to verify that you have no active configuration sessions. Save, commit, or discard any active configuration sessions before upgrading or downgrading the Cisco NX-OS software image on your device. On a device with dual supervisors, the active supervisor module cannot switch over to the standby supervisor module during the Cisco NX-OS software upgrade if you have an active configuration session. Ensure that the device has a route to the remote server. The device and the remote server must be in the same subnetwork if you do not have a router to route traffic between subnets. To verify connectivity to the remote server, use the ping command. switch# ping vrf management PING ( ): 56 data bytes 64 bytes from : icmp_seq=0 ttl=239 time= ms 64 bytes from : icmp_seq=1 ttl=239 time= ms 64 bytes from : icmp_seq=2 ttl=239 time= ms 64 bytes from : icmp_seq=3 ttl=239 time= ms 64 bytes from : icmp_seq=4 ttl=239 time=76.5 ms ping statistics packets transmitted, 5 packets received, 0.00% packet loss round-trip min/avg/max = 76.5/83.645/ ms For more information on configuration sessions, see the Cisco Nexus 3500 Series NX-OS System Management Configuration Guide. Prerequisites for Downgrading the Cisco NX-OS Software Downgrading the Cisco NX-OS software has the following prerequisites: Verify the compatibility of the software using the show incompatibility system bootflash:filename command. If an incompatibility exists, disable any features that are incompatible with the downgrade image before downgrading the software. Cisco NX-OS Software Upgrade Guidelines Note The Cisco Nexus 3500 Series NX-OS Release Notes contain specific upgrade guidelines for each release. See the Release Notes for the target upgrade release before starting the upgrade. Before attempting to upgrade to any software image, follow these guidelines: Schedule the upgrade when your network is stable and steady. Avoid any power interruption, which could corrupt the software image, during the installation procedure. The supervisor module must have connection on the console ports to maintain connectivity when switchovers occur during a software upgrade. See the Hardware Installation Guide for your specific chassis. 4

11 Upgrading or Downgrading the Cisco Nexus 3500 Series NX-OS Software Cisco NX-OS Software Downgrade Guidelines An upgrade to Cisco NX-OS Release 7.0(3)I7(2) is supported only from Cisco NX-OS Release 6.0(2)A8(7b) or higher releases. Note You must compact the Cisco NX-OS Release 7.0(3)I7(2) image before you upgrade from Cisco NX-OS Release 6.0(2)A8(x) to Cisco NX-OS Release 7.0(3)I7(2). The compaction can be done only during the scp file copy process. An upgrade to the following Cisco NX-OS releases is not supported: Cisco NX-OS Release 7.0(3)I2(x) Cisco NX-OS Release 7.0(3)I3(x) Cisco NX-OS Release 7.0(3)I4(x) Cisco NX-OS Release 7.0(3)I5(x) Cisco NX-OS Release 7.0(3)I6(x) Cisco NX-OS Release 7.0(3)I7(1) An upgrade from Cisco NX-OS Release 6.x to 7.x is disruptive for Cisco Nexus 3500 platform switches in a vpc environment when the STP global port type is configured as network or edge. To work around this issue, disable the spanning-tree port type {network edge} default command, perform the upgrade, and then re-enable this command on both switches in the vpc. Cisco NX-OS Software Downgrade Guidelines Before attempting to downgrade to an earlier software release, follow these guidelines: The supervisor module must have connection on the console ports to maintain connectivity when switchovers occur during a software downgrade. See the Hardware Installation Guide for your specific chassis. Cisco NX-OS automatically installs and enables the guest shell by default. However, if the device is reloaded with a Cisco NX-OS image that does not provide guest shell support, the existing guest shell is automatically removed and a %VMAN-2-INVALID_PACKAGE message is issued. As a best practice, remove the guest shell with the guestshell destroy command before downgrading to an earlier Cisco NX-OS image. Booting the Switch from the USB Starting from Release Rel 6.0(2)A8(4), you can optionally choose to boot the switch from an external flash memory drive at the loader prompt. The supported BIOS version for N3K-C3548P-10GX is and for N3K-C3548P-10G is Following are the various options for loading the image from an external flash memory drive: You can load the kickstart image from USB1 when either the USB1 slot is occupied or when both the USB slots are occupied. 5

12 Upgrading the Cisco NX-OS Software Upgrading or Downgrading the Cisco Nexus 3500 Series NX-OS Software Loader> boot usb1: <kickstart image> You can load the kickstart image from USB2 only when the USB2 slot is occupied. Loader> boot usb2: <kickstart image> You can load the kickstart image from USB2 when both the USB slots are occupied. Loader> boot usb2: <kickstart image> You can load the kickstart image and the system image from USB1 when only the USB1 slot is occupied or when both the USB slots are occupied. Loader> boot usb1: <kickstart image> usb1: <system image> You can load the kickstart image and the system image from USB2 when only the USB2 slot is occupied. Loader> boot usb2: <kickstart image> usb2:<system image> You can load the kickstart image and the system image from USB2 when both the USB slots are occupied. Loader> boot usb2: <kickstart image> usb2:<system image> Upgrading the Cisco NX-OS Software Note If an error message appears during the upgrade, the upgrade will fail because of the reason indicated. Procedure Step 1 Step 2 Step 3 Read the release notes for the software image file for any exceptions to this upgrade procedure. See the Cisco Nexus 3500 Series NX-OS Release Notes. Log in to the device on the console port connection. Ensure that the required space is available for the image files to be copied. switch# dir bootflash: May 10 14:43: lost+found/ May 10 15:57: n3500-uk9-kickstart a6.7.bin May 10 15:57: n3500-uk a6.7.bin... Usage for bootflash://sup-local bytes used bytes free bytes total Note We recommend that you have the image files for at least one previous release of the Cisco NX-OS software on the device to use if the new image files do not load successfully. Step 4 If you need more space on the device, delete unnecessary files to make space available. switch# delete bootflash:n3500-uk9-kickstart a6.7.bin 6

13 Upgrading or Downgrading the Cisco Nexus 3500 Series NX-OS Software Upgrading the Cisco NX-OS Software Step 5 Step 6 Upgrade the Cisco NX-OS software to Cisco NX-OS Release 6.0(2)A8(7b). Copy the software images to the device using a transfer protocol. You can use FTP, TFTP, SCP, or SFTP. switch# copy scp://user@scpserver.cisco.com//download/n3500-uk9-kickstart a8.7b.bin bootflash:n3500-uk9-kickstart a8.7b.bin switch# copy scp://user@scpserver.cisco.com//download/n3500-uk a8.7b.bin bootflash:n3500-uk a8.7b.bin Step 7 Check the impact of upgrading the software before actually performing the upgrade. switch# show install all impact kickstart bootflash:n3500-uk9-kickstart a8.7b.bin system bootflash:n3500-uk a8.7b.bin Installer is forced disruptive Verifying image bootflash:/n3500-uk9-kickstart a8.7b.bin for boot variable "kickstart". Verifying image bootflash:/cli1s.bin for boot variable "system". Verifying image type. Extracting "system" version from image bootflash:/cli1s.bin. Extracting "kickstart" version from image bootflash:/n3500-uk9-kickstart a8.7b.bin. Extracting "bios" version from image bootflash:/cli1s.bin. Collecting "running" plugin(s) information. Collecting plugin(s) information from "new" image. Performing runtime checks. [# ] 2% Recommended action:: "Module 1 might not be supported in the new image, it should be powered off before proceeding with install". Performing module support checks. Notifying services about system upgrade. Compatibility check is done: Module bootable Impact Install-type Reason no n/a n/a Incompatible image 7

14 Upgrading the Cisco NX-OS Software Upgrading or Downgrading the Cisco Nexus 3500 Series NX-OS Software Images will be upgraded according to following table: Module Image Running-Version New-Version Upg-Required system 6.0(2)A8(1) 6.0(2)A8(7b) no 1 kickstart 6.0(2)A8(1) 6.0(2)A8(7b) no 1 bios v1.9.0(10/13/2012) v1.9.0(10/13/2012) no 1 power-seq v2.1 v2.1 no Step 8 Save the running configuration to the startup configuration. switch# copy running-config startup-config Step 9 Upgrade the Cisco NX-OS software to Cisco NX-OS Release 6.0(2)A8(7b). switch# show ver Cisco Nexus Operating System (NX-OS) Software TAC support: Documents: s_home.html Copyright (c) , Cisco Systems, Inc. All rights reserved. The copyrights to certain works contained herein are owned by other third parties and are used and distributed under license. Some parts of this software are covered under the GNU Public License. A copy of the license is available at Software BIOS: version loader: version N/A kickstart: version 6.0(2)A8(7b) system: version 6.0(2)A8(7b) Power Sequencer Firmware: Module 1: version v2.1 BIOS compile time: 12/26/2014 kickstart image file is: bootflash:///n3500-uk9-kickstart a8.7b.bin kickstart compile time: 12/7/ :00:00 [12/08/ :40:08] system image file is: bootflash:///n3500-uk a8.7b.bin system compile time: 12/7/ :00:00 [12/08/ :11:52] Hardware cisco Nexus 3548 Chassis ("48x10GE Supervisor") Intel(R) Pentium(R) 2.00GHz with kb of memory. Processor Board ID FOC19023PMB Device name: SW3-MTC-2023 bootflash: kb Kernel uptime is 0 day(s), 0 hour(s), 51 minute(s), 33 second(s) Last reset at usecs after Mon Jan 15 17:00: Reason: Reset due to upgrade System version: 6.0(2)A8(1) Service: plugin Core Plugin, Ethernet Plugin switch# Step 10 Compact the Cisco NX-OS software image to Cisco NX-OS Release 7.0(3)I7(x). 8

15 Upgrading or Downgrading the Cisco Nexus 3500 Series NX-OS Software Upgrading the Cisco NX-OS Software switch# copy bootflash: compact vrf management The authenticity of host 'scpserver.cisco.com' can't be established. RSA key fingerprint is SHA1:88:08:22:02:a7:c1:3a:f9:e0:b5:3e:49:9f:ee:82:68:aa:2a:b8:55. Are you sure you want to continue connecting (yes/no)? yes Warning: Permanently added 'scpserver.cisco.com' (RSA) to the list of known hosts. password: nxos i7.2.bin 100% 845MB 5.4MB/s 02:38 Copy complete, now saving to disk (please wait)... switch# switch# dir bootflash: i nxos Nov 23 12:20: nxos i7.2.bin switch# Step 11 Upgrade the Cisco NX-OS software using the install all nxos bootflash:filename [no-reload non-disruptive non-interruptive serial] command. switch# install all nxos bootflash:nxos i7.2.bin Verifying image bootflash:/nxos i7.2.bin for boot variable "nxos". Verifying image type. Extracting "nxos" version from image bootflash:/nxos i7.2.bin. Extracting "bios" version from image bootflash:/nxos i7.2.bin. Performing runtime checks. Performing module support checks. Notifying services about system upgrade. Compatibility check is done: Module bootable Impact Install-type Reason yes disruptive reset Unsupported in new image, module needs to be powered off Images will be upgraded according to following table: Module Image Running-Version New-Version Upg-Required kickstart 6.0(2)A8(7b) 7.0(3)I7(2) yes 1 bios v2.0.6(12/26/2014) v4.2.0(09/23/2017) yes 1 power-seq v2.1 v2.1 no Switch will be reloaded for disruptive upgrade. Do you want to continue with the installation (y/n)? [n] y Time Stamp: Thu Nov 23 12:22:

16 Downgrading to an Earlier Software Release Upgrading or Downgrading the Cisco Nexus 3500 Series NX-OS Software Install is in progress, please wait. Performing runtime checks. Setting boot variables. Performing configuration copy. Module 1: Refreshing compact flash and upgrading bios/loader/bootrom/power-seq. Warning: please do not remove or power off the module at this time. Note: Power-seq upgrade needs a power-cycle to take into effect. On success of power-seq upgrade, SWITCH OFF THE POWER to the system and then, power it up. [# ] 0% Time Stamp: Thu Nov 23 12:25: Finishing the upgrade, switch will reboot in 10 seconds. switch# Note If you enter the install all command without specifying a filename, the command performs a compatibility check, notifies you of the modules that will be upgraded, and confirms that you want to continue with the installation. If you choose to proceed, it installs the NXOS software image that is currently running on the switch and upgrades the BIOS of various modules from the running image if required. Step 12 (Optional) Display the entire upgrade process. switch# show install all status Step 13 (Optional) Log in and verify that the device is running the required software version. switch# show version Step 14 (Optional) If necessary, install any licenses to ensure that the required features are available on the device. See the Cisco NX-OS Licensing Guide. Downgrading to an Earlier Software Release Procedure Step 1 Step 2 Step 3 Read the release notes for the software image file for any exceptions to this downgrade procedure. See the Cisco Nexus 3500 Series NX-OS Release Notes. Log in to the device on the console port connection. Verify that the image files for the downgrade are present on the device bootflash:. switch# dir bootflash: May 10 14:43: lost+found/ May 10 15:57: n3500-uk9-kickstart a6.7.bin May 10 15:57: n3500-uk a6.7.bin 10

17 Upgrading or Downgrading the Cisco Nexus 3500 Series NX-OS Software Downgrading to an Earlier Software Release... Usage for bootflash://sup-local bytes used bytes free bytes total Step 4 Step 5 If the software image file is not present, log in to Cisco.com, choose the software image file for your device from the following URL, and download it to a file server: Note If you need more space on the device bootflash:, use the delete command to remove unnecessary files. Copy the software images to the device using a transfer protocol. You can use FTP, TFTP, SCP, or SFTP. switch# copy scp://user@scpserver.cisco.com//download/n3500-uk9-kickstart a8.9.bin bootflash:n3500-uk9-kickstart a8.9.bin switch# copy scp://user@scpserver.cisco.com//download/n3500-uk a8.9.bin bootflash:n3500-uk a8.9.bin Step 6 Check for any software incompatibilities. switch# show incompatibility system bootflash:n3500-uk a8.9.bin Checking incompatible configuration(s) No incompatible configurations The resulting output displays any incompatibilities and remedies. Step 7 Erase the startup configuration file. switch# write erase Step 8 Erase the boot variable definitions and the IPv4 configuration on the mgmt0 interface. switch# write erase boot Step 9 Step 10 Disable any features that are incompatible with the downgrade images. Save the running configuration to the startup configuration. switch# copy running-config startup-config Step 11 Downgrade the Cisco NX-OS software. Note Make sure to use the no-save and bios-force options when performing the downgrade. switch# install all kickstart bootflash:n3500-uk9-kickstart a8.9.bin system bootflash:n3500-uk a8.9.bin no-save bios-force Installer is forced disruptive Verifying image bootflash:/n3500-uk9-kickstart a8.9.bin for boot variable "kickstart". Verifying image bootflash:/n3500-uk a8.9.bin for boot variable "system". Verifying image type. 11

18 Downgrading to an Earlier Software Release Upgrading or Downgrading the Cisco Nexus 3500 Series NX-OS Software Extracting "system" version from image bootflash:/n3500-uk a8.9.bin. Extracting "kickstart" version from image bootflash:/n3500-uk9-kickstart a8.9.bin. Extracting "bios" version from image bootflash:/n3500-uk a8.9.bin. Collecting "running" plugin(s) information. Collecting plugin(s) information from "new" image. Performing runtime checks. [# ] 100% -- SUCCESS Note If you enter the install all command without specifying a filename, the command performs a compatibility check, notifies you of the modules that will be upgraded, and confirms that you want to continue with the installation. If you choose to proceed, it installs the Cisco NX-OS software image that is currently running on the switch and upgrades the BIOS of various modules from the running image if required. Step 12 (Optional) Display the entire downgrade process. Example: switch# show install all status Step 13 (Optional) Log in and verify that the device is running the required software version. switch# show version 12