VDX6940-144S, VDX 6940-96S & VDX 6940-64S with a newer hardware component can experience sudden reload if the device is running with NOS version without the fixes.
To identify a newer hardware component, execute “show chassis” CLI and verify Factory Part Num, if the last 2 digits are 11 or higher, it is running with the affected hardware component as below.
sw0# show chassis
Factory Part Num: 40-1001106-11
These VDX 6940 product family with the newer hardware component will come with a compatible NOS version from manufacturing and firmware downgrade and upgrade cases have been handled as below:
1. Firmware download to a non uboot fix NOS version [Ex: NOS7.0.1c] will NOT be supported and blocked.
sw0# firmware download [default-config] scp user <UN> password <PW> host 10.10.10.10 directory <ImageDir>/nos7.0.1c
Performing system sanity check... A newer hardware component has been detected, thus firmware download is
blocked to avoid degrading the system performance of the BR-VDX6940-144S platform.
The preinstall script failed.
2. Firmware download to uboot fix NOS version [Ex: NOS7.2.0] will be supported.
sw0# firmware download [default-config] scp user <UN> password <PW> host 10.10.10.10 directory <ImgaeDir>/nos7.2.0/
Performing system sanity check... This command will cause a cold/disruptive reboot and will require that
existing telnet, secure telnet or SSH sessions be restarted.
Do you want to continue? [y/n]:
3. Firmware Upgrade/Downgrade when a cluster has a variety of products including affected products with a newer hardware component.
This is to ensure avoiding a partial cluster upgrade with the other half blocked on older releases due to other nodes in the cluster failing upgrade due to the presence of the issue on any single applicable node.
If planning to perform a cluster wide firmware download operation, then it would be better to identify the vulnerability with this issue on any affected product by verifying “Factory Part Num” as mentioned above prior to the upgrade.