Downgrading OS Software
Prior to downgrading software, please make sure the following prerequisites are met.
Log in to the switch via the CLI using the console port.
Backup configuration by following these steps.
Disable paging of CLI output.
switch(config)# no clidefaultpaging enableDisplay commands to recreate current running configuration.
switch(config)# show running-configCopy the output to a text file.
Log in to your system to obtain its product number.
switch(config) # show inventoryLog in to NVIDIA Enterprise Support Portal and download the relevant MLNX-OS version to your system type
Log in to your system via the CLI.
Change to Config mode.
switch> enableswitch# configure terminalswitch(config) #Delete all previous images from the Images available to be installed prior to fetching the new image.
Fetch the desired software image.
switch(config) # image fetch scp://username:password@192.168.10.125/var/www/html/<image_name>100.0%[#################################################################]
The procedure described below assumes that booting and running is done from Partition 1 and the downgrade procedure is performed on Partition 2.
Log in to your system via the CLI as admin.
Enter config mode.
switch> enableswitch# configure terminal- Display all image files on the system. null
Install the fetched image.
switch(config) # image install <image_name> Step1of4: Verify Image100% [#################################################################] Step2of4: Uncompress Image100.0% [#################################################################] Step3of4: Create Filesystems100.0% [#################################################################] Step4of4: Extract Image100.0% [#################################################################]- Display all image files on the system. null
Configure the boot location to be the other (next) partition.
switch(config) # image boot nextWarningThere are two installed images on the system. Therefore, if one of the images gets corrupted (due to power interruption, for example), in the next reboot the image will go up from the second partition.
WarningIf you are downgrading to an older software version which has never been run yet on the switch, use the following command sequence as well.
switch(config) # no boot next fallback-reboot enableswitch(config) # configuration writeReload.
switch(config) # reload
The system saves a backup configuration file when upgrading from an older software version to a newer one. If the system returns to the older software partition, it uses this backup configuration file.
All configuration changes done with the new software are lost when returning to the older software version.
There are 2 instances where the backup configuration file does not exist:
The user has run “reset factory” command, which clears all configuration files in the system
The user has run “configuration switch-to” to a configuration file with different name then the backup file
Note that the configuration file becomes empty if the system is downgraded to a software version which has never been installed yet.
To allow switching partition to the older software version for the 2 aforementioned cases only, follow the steps below.
Run the following command.
switch(config)# no boot next fallback-reboot enableSet the boot partition.
switch(config)# image boot nextSave the configuration.
switch(config)# configuration writeReload the system.
switch(config)# reload