Each device is shipped with the Cisco NX-OS software. The Cisco NX-OS software consists 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.

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.

Cisco recommends performing a Nexus Health and Configuration Check before performing an upgrade. The benefits include identification of potential issues, susceptible Field Notices and Security Vulnerabilities, missing recommended configurations and so on. For more information about the procedure, see Perform Nexus Health and Configuration Check.

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.

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.

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.

• An upgrade to Cisco NX-OS Release 9.2(x) is supported only from Cisco NX-OS Release 6.0(2)A8(9) or higher releases.

  Note	You must compact the Cisco NX-OS Release image before you upgrade from Cisco NX-OS Release 6.0(2)A8(7b) to Cisco NX-OS Release 9.2(1). The image can be compacted only during the scp file copy process.

• Beginning with Cisco NX-OS Release 9.2(1), a simplified NX-OS numbering format is used for the platforms that are supported in the release. In order to support a software upgrade from releases prior to Release 7.0(3)I7(4) that have the old release format, an installer feature supplies an I9(1) label as a suffix to the actual release during the install all operation. This label is printed as part of the image during the install operation from any release prior to 7.0(3)I7(4) to Release 9.2(1), and it can be ignored. See the following example.

  switch# install all nxos bootflash:nxos.9.2.1.bin
  Installer will perform compatibility check first. Please wait. 
  Installer is forced disruptive
  
  Verifying image bootflash:/nxos.9.2.1.bin for boot variable "nxos".
  [####################] 100% -- SUCCESS
  
  Verifying image type.
  [####################] 100% -- SUCCESS
  
  Preparing "nxos" version info using image bootflash:/nxos.9.2.1.bin.
  [####################] 100% -- SUCCESS
  
  Preparing "bios" version info using image bootflash:/nxos.9.2.1.bin.
  [####################] 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       Incompatible image for ISSU
  
  Images will be upgraded according to following table:
  Module   Image                 Running-Version(pri:alt)  New-Version          Upg-Required
  ------  -------  -------------------------------------- --------------------  ------------
    1      nxos                               7.0(3)I7(3)          9.2(1)I9(1)           yes
    1      bios     v05.31(05/17/2018):v05.26(11/06/2017)   v05.31(05/17/2018)            no
  
  
  Switch will be reloaded for disruptive upgrade.
  Do you want to continue with the installation (y/n)?  [n] y
  

• 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.

• In Cisco NX-OS Release 9.2(2) Flexlink is supported on Cisco N3K-C3548P-XL (MTC/MTC-CR/MTC-XL) Platform switches.

• In Cisco NX-OS Release 9.2(3) and 9.2(4), Flexlink is not supported on Cisco N3K-C3548P-XL (MTC/MTC-CR/MTC-XL) Platform switches.

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.

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.

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.

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, it is 1.0.11. Following are the various options for loading the image from an external flash memory drive:

• You can load the image from USB1 when either the USB1 slot is occupied or when both the USB slots are occupied.

  Loader> boot usb1: <image>

• You can load the image from USB2 only when the USB2 slot is occupied.

  Loader> boot usb2: <image>

• You can load the image from USB2 when both the USB slots are occupied.

  Loader> boot usb2: <image>

• You can load the image from USB1 when only the USB1 slot is occupied or when both the USB slots are occupied.

• You can load the image from USB2 when only the USB2 slot is occupied.

• You can load the image from USB2 when both the USB slots are occupied.