[c-nsp] Nexus 7000 - vPC during NX-OS upgrade (ISSU)

[Lincoln Dale]

On 28/01/2011, at 10:12 AM, Manu Chao wrote:
> Because FPGA/EPLD upgrade operation is a disruptive operation, it is not always possible to upgrade both software and firmware.
> --> Do you think or may be do you know if it is an issue having an up-to-date NX-OS 5.x with old EPLD release 4.x?

generally speaking, EPLD upgrades are not necessary.

key here is understanding what EPLDs are.  they are basically microcode changes - either in management plane on a module (e.g. power-management on a module) or a programmable data-plane component (e.g. crypto engine that implements 802.1AE, or vnTag support on specific modules).

you may need to upgrade EPLD on a given module if you are using some specific functionality that we have fixed a bug on.  an example of this may be some key-change enhancements to 802.1AE crypto.
you may need to upgrade EPLD on a given module if you wish to use a feature that a new(er) EPLD provides - e.g. PVLAN trunk, vnTag/FEX on N7K-M132 I/O module.

but otherwise, there is generally no requirement to proactively upgrade EPLD with every release.
they are forwards/backwards compatible.  you don't need to be running latest EPLD nor do all modules in a system need to be running the same EPLD.


cheers,

lincoln.