Symptom

A Nexus 3000, 3100, or 3500 device fails to boot up after an NX-OS software upgrade from an NX-OS software release prior to 7.0(3)I7(7) or 9.2(4) to an NX-OS software release in the 9.3(x) train (such as 9.3(1), 9.3(2), 9.3(3), etc.) using a compact image (an NX-OS binary image file that has had its filesize reduced through the NX-OS Compact Image Procedure). The device will be stuck in a boot loop and will output a message similar to the following on the console while attempting to boot up: Image valid MD5Sum mismatch File does not exist, boot failed.

Conditions

This issue can be observed under the following conditions: 1. Issue is observed on a Nexus 3000 (3048, 3064, etc.), 3100 (3132, 3172, etc.), or 3500 (3548-10G, 3548-10GX, etc.) device. 2. NX-OS software upgrade was performed from an NX-OS software release prior to 7.0(3)I7(7) (such as 7.0(3)I7(3), 7.0(3)I7(6), etc.) or 9.2(4) (such as 9.2(1), 9.2(3), etc.) to an NX-OS software release in the 9.3(x) train (such as 9.3(1), 9.3(2), 9.3(3), etc.) 3. NX-OS Compact Image Procedure was invoked on the NX-OS software binary image file for an NX-OS software release in the 9.3(x) train (such as 9.3(1), 9.3(2), 9.3(3), etc.).

Workaround

Invoking the NX-OS Compact Image Procedure against an NX-OS software binary image file in the 9.3(x) train or higher (such as 9.3(1), 9.3(2), 9.3(3), etc.) is not supported until NX-OS software release 7.0(3)I7(7) or 9.2(4). In order to invoke the NX-OS Compact Image Procedure against an NX-OS software binary image file in the 9.3(x) train or higher, one must upgrade to NX-OS software release 7.0(3)I7(7) (or higher) or 9.2(4) (or higher). To recover a Nexus switch from this condition, follow the below procedure: 1. Break the device out of its boot loop into the loader prompt by repeatedly entering the "Control+C" break sequence until you see the "loader>" prompt, as shown below. loader> 2. Use the "boot" command to boot the device using the NX-OS software release that you upgraded from. For example, if you attempted to upgrade from NX-OS 7.0(3)I7(4) to 9.3(3), you would boot using the NX-OS 7.0(3)I7(4) binary image file. loader> boot bootflash:nxos.7.0.3.I7.4.bin 3. The device should boot into NX-OS successfully. Once this is done, upgrade the NX-OS software release of the device to 7.0(3)I7(7) (or later) or 9.2(4) (or later). 4. Invoke the NX-OS Compact Image Procedure against the NX-OS software binary image file for the desired NX-OS software release in the 9.3(x) train (such as 9.3(1), 9.3(2), 9.3(3), etc.) or later. Details about the NX-OS Compact Image Procedure can be found in the following document: https://www.cisco.com/c/en/us/support/docs/switches/nexus-3000-series-switches/215781-nexus-3000-3100-and-3500-nx-os-compact.html 5. Upgrade to the desired NX-OS software release in the 9.3(x) train (9.3(1), 9.3(2), 9.3(3), etc.) or later using the compacted NX-OS binary image file created in the previous step through the command as shown below. switch# install all nxos bootflash:nxos.9.3.3.bin

Further Problem Description