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

Preface

This preface includes the following sections:

• Audience
• Document Conventions
• Related Documentation for Cisco Nexus 3000 Series Switches
• Documentation Feedback
• Communications, Services, and Additional Information

Audience

This publication is for network administrators who install, configure, and maintain Cisco Nexus switches.

Document Conventions

Command descriptions use the following conventions:

Examples use the following conventions:

Related Documentation for Cisco Nexus 3000 Series Switches

The entire Cisco Nexus 3000 Series switch documentation set is available at the following URL: https://www.cisco.com/c/en/us/support/switches/nexus-3000-series-switches/

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. Cisco appreciates your feedback.

Communications, Services, and Additional Information

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Cisco Bug Search Tool

Cisco Bug Search Tool (BST) is a web-based tool that acts as a gateway to the Cisco bug tracking system that maintains a comprehensive list of defects and vulnerabilities in Cisco products and software. BST provides you with detailed defect information about your products and software.

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

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
• Compact Image for Cisco Nexus 3000, 3100, and 3500, on page 6
• Booting the Switch from the USB, on page 9
• Upgrading the Cisco NX-OS Software, on page 9
• Downgrading to an Earlier Software Release, on page 13

About the Software Image

Each device is shipped with the Cisco NX-OS software. The Cisco NX-OS software consists of a single NXOS software image. Only this image is required to load the Cisco NX-OS operating system. This image runs on all Cisco Nexus 3500 Series switches.

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:

• 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 172.18.217.1 vrf management
PING 172.18.217.1 (172.18.217.1): 56 data bytes
64 bytes from 172.18.217.1: icmp_seq=0 ttl=239 time=106.647 ms
64 bytes from 172.18.217.1: icmp_seq=1 ttl=239 time=76.807 ms
64 bytes from 172.18.217.1: icmp_seq=2 ttl=239 time=76.593 ms
64 bytes from 172.18.217.1: icmp_seq=3 ttl=239 time=81.679 ms
64 bytes from 172.18.217.1: icmp_seq=4 ttl=239 time=76.5 ms
--- 172.18.217.1 ping statistics ---
5 packets transmitted, 5 packets received, 0.00% packet loss
round-trip min/avg/max = 76.5/83.645/106.647 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.
• IGMP snooping must be configured if there is a PIM enabled SVI present for the VLAN. It is recommended to enable IGMP snooping on VLAN first and then enable the PIM on SVI.
• 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 image can be compacted 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 Nexus 3548 and 3548-X switches must run a compact NX-OS software image due to limited bootflash space. This compact image can be created using the NX-OS Compact Image procedure; alternatively, a compact NX-OS software image can be downloaded directly from Cisco's Software Download website. This requirement does not apply to the Cisco Nexus 3548-XL switch.
• The MD5/SHA512 checksum published on Cisco's Software Download website for a compact NX-OS software image may not match the MD5/SHA512 checksum of a compact image created through the NX-OS Compact Image procedure.

The following limitations are applicable when you upgrade from Cisco NX-OS Releases 6.0(2)A8(7b), 6.0(2)A8(8), or 6.0(2)A8(9):

• If Cisco Catalyst devices are connected via a vPC to a pair of Nexus 3500 switches with the vPC peer switch feature enabled, a partial or complete network outage may be caused as a result of the Cisco Catalyst devices error-disabling their port-channel interfaces due to EtherChannel Guard. To prevent this from happening, it is recommended that you must temporarily disable the EtherChannel Guard feature on vPC-connected Cisco Catalyst devices while the Nexus 3500 devices are being upgraded. For more information, see CSCvt02249.

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.

Compact Image for Cisco Nexus 3000, 3100, and 3500

Early models of Cisco Nexus 3000, 3100, and 3500 Series switches with a model number that does not end in -XL have 1.4 to 1.6 gigabytes of storage space allocated to the bootflash. Over time, the file size of NX-OS software images has steadily increased to be over 1 gigabyte. As a result, it is difficult for Nexus 3000, 3100, and 3500 Series switches with a model number that does not end in -XL to simultaneously store more than one full NX-OS binary image at a time. Therefore, administrators cannot follow the standard NX-OS software upgrade procedure on Nexus 3000, 3100, and 3500 Series switches with a model number that does not end in -XL that is used for other Nexus platforms, such as Nexus 5000, 6000, 7000, and 9000 Series switches.

Starting with NX-OS software release 7.0(3)I3(1), the file size of NX-OS software images can be reduced through the NX-OS Compact Image procedure. This is a non-disruptive procedure that does not affect the switch's control plane or ability to forward data plane traffic.

Compact NX-OS Software Images on Cisco's Software Download Website

Compact NX-OS software images are available for download on Cisco's Software Download website for a few NX-OS software releases. These compact images have a published MD5/SHA512 checksum that can be used to verify the integrity of the NX-OS binary image file. The compact NX-OS software images can be downloaded from Cisco's Software Download website for the following NX-OS software releases:

• 9.3(4) and later
• 9.2(4)
• 7.0(3)I7(8) and later

Note: The MD5/SHA512 checksum published on Cisco's Software Download website for a compact NX-OS software image may not match the MD5/SHA512 checksum of a compact image created through the NX-OS Compact Image procedure.

Compact Image to be Run for Different Switch Models

The following table describes the appropriate compact image to be run for each applicable model of switch, using NX-OS software release 7.0(3)I7(8) as an example.

Table 2: Compact Image Table for Each Cisco Nexus 3000, 3100, and 3500 Series Platform

NX-OS Compact Image Procedure

There are two ways to initiate the NX-OS Compact Image procedure. The following subsections describe each option in further detail.

NX-OS Compact Image Procedure on Bootflash/USB

Starting with NX-OS software release 7.0(3)I3(1), you can use the install all command with the compact option to initiate the NX-OS Compact Image procedure on an image stored in the switch's bootflash or an attached USB drive. This can also be performed on an NX-OS software image that the switch is currently booted from - however, a minimum of 750 MB of free space on the switch's bootflash is required to compact the currently booted image.

An example of how to initiate the NX-OS Compact Image procedure on an NX-OS software image stored on the switch's bootflash is as follows:

switch# install all nxos booftflash:nxos.7.0.3.I7.8.bin compact

NX-OS Compact Image Procedure Through SCP

Starting with NX-OS software release 7.0(3)I5(2), the NX-OS Compact Image procedure can be initiated while copying the image to the switch's bootflash or an attached USB drive with SCP (Secure Copy Protocol) using an additional option in the copy command. The compact option in the copy command overrides the bootflash space limitation as the image is compacted at the time of transferring the image to the switch's bootflash or an attached USB drive. This option is only supported with SCP - other protocols (such as SFTP [Secure File Transfer Protocol] and FTP [File Transfer Protocol]) are not supported.

An example of how to initiate the NX-OS Compact Image procedure while copying an NX-OS software image to the switch's bootflash through SCP is as follows:

switch# copy scp://username@192.0.2.100/nxos.7.0.3.I7.8.bin bootflash:nxos.7.0.3.I7.8.bin compact vrf management

NX-OS Compact Image Procedure Sequence

The sequence of compacting NX-OS software images is important. You cannot compact the currently loaded NX-OS software image if you have another NX-OS software image present on the bootflash due to the limited bootflash size of the switch.

First, you should compact the currently booted image on the bootflash using the NX-OS Compact Image Procedure on Bootflash/USB method previously described. Next, you should copy the desired NX-OS software image to the switch's bootflash using the NX-OS Compact Image Procedure through SCP method previously described, if possible. If this option is not possible, because you are upgrading to an NX-OS software release prior to 7.0(3)I5(2), you should copy the desired NX-OS software image to the switch's bootflash normally, then use the NX-OS Compact Image Procedure on Bootflash/USB method previously described to compact the image.

The minimum required free space to compact a non-booted image is 450 MB of free space on the switch's bootflash. If the free space available on the switch's bootflash is less than 450 MB after copying the target image, then the target image needs to be compacted using an attached USB drive or through the NX-OS Compact Image Procedure through SCP method previously described.

NX-OS Compact Image Platform Groups

The NX-OS Compact Image procedure described in this document is applicable to three separate platform groups:

• Nexus 3000 devices (N3K-C3048, N3K-C3064, and so on)
• Nexus 3100 devices (N3K-C3132, N3K-C3172, and so on)
• Nexus 3500 devices (N3K-C3524, N3K-C3548, and so on)

A compacted NX-OS binary image file can be re-used among other devices within the same platform group. However, a compact NX-OS binary image file cannot be used on devices that belong to a different platform group.

For example, consider a scenario where you have four Nexus 3000 devices of the following models:

• N3K-C3048TP-1GE
• N3K-C3064PQ-10GE
• N3K-C3172PQ-40GX
• N3K-C3548P-10G

An NX-OS binary image file compacted on the N3K-C3048TP-1GE can be transferred directly to the bootflash of the N3K-C3064PQ-10GE through a file transfer protocol of your choice (provided there is enough room on the N3K-C3064PQ-10GE). Furthermore, the N3K-C3064PQ-10GE can be upgraded with the use of this compact NX-OS binary image file through a supported method. However, the same compact NX-OS binary image file cannot be used to upgrade the N3K-C3172PQ-40GX and N3K-C3548P-10G devices. The NX-OS Compact Image procedure must be executed on both N3K-C3172PQ-40GX and N3K-C3548P-10G devices separately.

This compatibility between Nexus devices within the same platform group can be used to optimize the NX-OS software upgrade of a large number of devices. For example, if you have 100 N3K-C3048TP-1GE devices, you can use the NX-OS Compact Image procedure on a single device, then transfer the compact NX-OS binary image file to the resulting 99 devices. There is no need to perform the NX-OS Compact Image procedure on all 100 devices.

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 the Cisco Nexus 3548P-10GX switch is 2.0.8 and for the Cisco Nexus 3548P-10G switch is 1.0.11. 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.

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.

Before you begin

The following procedure is an example upgrade from Cisco NX-OS Release 6.x to Cisco NX-OS Release 7.x that requires an intermediate upgrade to 6.0(2)A8(7b). If you are upgrading from a 7.x release to another 7.x release, see the Cisco Nexus 3500 Series NX-OS Release Notes for your desired target release to determine if any intermediate upgrades are required.

Procedure

1. 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.
2. Log in to the device on the console port connection.
3. Ensure that the required space is available for the image files to be copied.

switch# dir bootflash:
9341 Aug 05 15:18:04 2020 .n3k_pre_single_img_upd_config
4096 Jan 01 21:20:45 2011 .patch/
4096 May 11 14:00:34 2020 .rpmstore/
4096 May 11 14:01:03 2020 .swtam/
4096 May 06 17:40:27 2020 eem_snapshots/
4096 Sep 20 22:32:55 2011 home/
4096 Aug 23 17:32:21 2019 logflash/
36825088 Sep 12 13:11:09 2020 n3500-uk9-kickstart.6.0.2.A6.2a.bin
36825088 Sep 12 12:27:25 2020 n3500-uk9-kickstart.6.0.2.A6.7.bin
179930562 Sep 12 13:11:48 2020 n3500-uk9.6.0.2.A6.2a.bin
180439452 Sep 12 12:31:05 2020 n3500-uk9.6.0.2.A6.7.bin
4096 Jan 01 21:20:43 2011 vdc_2/
4096 Jan 01 21:20:43 2011 vdc_3/
4096 Jan 01 21:20:43 2011 vdc_4/
4096 Jan 01 21:20:49 2011 virtual-instance/
Usage for bootflash://sup-local
515342336 bytes used
1379827712 bytes free
1895170048 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.

4. If you need more space on the device, delete unnecessary files to make space available.

switch# delete bootflash:n3500-uk9-kickstart.6.0.2.A6.2a.bin
switch# delete bootflash:n3500-uk9.6.0.2.A6.2a.bin

5. 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.6.0.2.A8.7b.bin bootflash:n3500-uk9-kickstart.6.0.2.A8.7b.bin
switch# copy scp://user@scpserver.cisco.com//download/n3500-uk9.6.0.2.A8.7b.bin bootflash:n3500-uk9.6.0.2.A8.7b.bin

6. Check the impact of upgrading the software before actually performing the upgrade.

switch# show install all impact kickstart bootflash:n3500-uk9-kickstart.6.0.2.A8.7b.bin system
bootflash:n3500-uk9.6.0.2.A8.7b.bin
Installer is forced disruptive
Verifying image bootflash:/n3500-uk9-kickstart.6.0.2.A8.7b.bin for boot variable "kickstart". [########################################] 100% -- SUCCESS

Verifying image bootflash:/clils.bin for boot variable "system". [##################################################] 100% -- SUCCESS

Verifying image type.
[##################################################] 100% -- SUCCESS

Extracting "system" version from image bootflash:/clils.bin. [####################################################] 100% -- SUCCESS

Extracting "kickstart" version from image bootflash:/n3500-uk9-kickstart.6.0.2.A8.7b.bin. [######################################################] 100% -- SUCCESS

Extracting "bios" version from image bootflash:/clils.bin. [########################################################] 100% -- SUCCESS

Collecting "running" plugin(s) information. [##########################################################] 100% -- SUCCESS

Collecting plugin(s) information from "new" image. [####################################################] 100% -- SUCCESS

Performing runtime checks.
[##################################################################] 100% -- SUCCESS

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.
[##################################################] 100% -- SUCCESS

Notifying services about system upgrade.
[####################################################################] 100% -- SUCCESS

Compatibility check is done:
Module bootable Impact Install-type Reason
1 no n/a n/a Incompatible image

Images will be upgraded according to following table:

| Module | Image | Running-Version | New-Version | Upg-Required |
| :--: | :--: | :--: | :--: | :--: |
| 1 | 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 |

Note: The system and kickstart images are not available with Cisco Release NX-OS 7.x. So, the show install all impact command does not apply while upgrading from Cisco NX-OS Release 6.x to Cisco NX-OS 7.x.
Save the running configuration to the startup configuration.

switch# copy running-config startup-config

Upgrade the Cisco NX-OS software to Cisco NX-OS Release 6.0(2)A8(7b).

switch# install all kickstart bootflash:n3500-uk9-kickstart.6.0.2.A8.7b.bin system bootflash:n3500-uk9.6.0.2.A8.7b.bin

Compact the Cisco NX-OS software image to Cisco NX-OS Release 7.0(3)17(x).

switch# copy scp://user@scpserver.cisco.com//download/nxos.7.0.3.I7.8.bin
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.
user@scpserver.cisco.com's password:
nxos.7.0.3.I7.8.bin
$100% 937MB 5.4MB/s 02:38
Copy complete, now saving to disk (please wait)...
switch#
switch# dir bootflash: | include nxos
457410062 Sep 12 14:37:46 2020 nxos.7.0.3.I7.8.bin
switch#

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.7.0.3.I7.8.bin
Installer is forced disruptive
Verifying image bootflash:/nxos.7.0.3.I7.8.bin for boot variable "nxos".
[########################################] 100% -- SUCCESS

Verifying image type.
[########################################] 100% -- SUCCESS
Extracting "nxos" version from image bootflash:/nxos.7.0.3.I7.8.bin.
[########################################] 100% -- SUCCESS
Extracting "bios" version from image bootflash:/nxos.7.0.3.I7.8.bin.
[########################################] 100% -- SUCCESS
Performing runtime checks.
[########################################] 100% -- SUCCESS
Performing module support checks.
[########################################] 100% -- SUCCESS
Notifying services about system upgrade.
[########################################] 100% -- SUCCESS

Compatibility check is done:
Module bootable Impact Install-type Reason
1 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 |
| :--: | :--: | :--: | :--: | :--: | :--: |
| 1 | kickstart | 6.0 (2) A8 (11b) | 7.0 (3) I7 (8) |  | yes |
| 1 | bios | v5.4.0(10/23/2019) | v5.4.0(10/23/2019) |  | no |
| 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: Sat Sep 12 14:42:15 2020
Install is in progress, please wait.
Performing runtime checks.
[###########################################] 100% -- SUCCESS
Setting boot variables.
[###########################################] 100% -- SUCCESS
Performing configuration copy.
[###########################################] 100% -- SUCCESS
Time Stamp: Sat Sep 12 14:42:43 2020
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.

(Optional) Log in and verify that the device is running the required software version.

switch# show version

(Optional) If necessary, install any licenses to ensure that the required features are available on the device. See the Cisco NX-OS Licensing Guide.