[c-nsp] Nexus Lack of Functionality Parity

[Lukas Tribus]

Hello Mike,


On Mon, 15 Jul 2019 at 16:17, Mike Hammett <cisco-nsp at ics-il.net> wrote:
>
> Is it common for there to be a lack of functionality parity across the Nexus line?

Yes, default logging on the Nexus is different on different series
switches and at least on the 7k/9k is also a giant trap (a Nexus 9k by
default *disables mac address learning for 120s in a vlan* if it
doesn't like the amount of mac moves, but DOES NOT LOG that it
happened).

For full mac logging on 7k/9k series:
logging level l2fm 5

Or less verbose, but still logging when mac address learning is
disabled (%L2FM-3-L2FM_MAC_FLAP_DISABLE_LEARN), setting l2fm log level
to 3 should suffice (theoretically):
logging level l2fm 3


As per:
https://www.cisco.com/c/en/us/support/docs/switches/nexus-7000-series-switches/200424-Nexus-L2FM-4-L2FM-MAC-MOVE-syslog-expla.html

IOS: mac address table notification mac-move
N3K: mac address table notification mac-move ; logging level fwm 6 ;
logging monitor 6
N4K: mac address table notification mac-move ; logging level fwm 6 ;
logging monitor 6
N5K/N6K: mac address table notification mac-move ; logging level fwm
6; logging monitor 6
N7K/N9K: logging level l2fm 5


Also see:
https://www.cisco.com/c/en/us/support/docs/ios-nx-os-software/nx-os-software/213906-nexus-9000-mac-move-troubleshooting-and.html


Who could have known that datacenter operators want to know when the
switch stops learning mac address on an entire vlan for 120 seconds...



cheers,
lukas