I have over 100 N2000 switches in my network, almost all connected to Cisco 4500x switches. As of firmware 6.2.6.6, the N2000s no longer show up in a "sh cdp neigh" on the Cisco switch.
Additionally, running a show cdp traffic on the Cisco switch shows a high number of invalid packets. Again, only switches that have Dell switches on 6.2.6.6 below them. 6.2.0.5 and 6.1.1.7 seem to be fine.
Is this a known issue? Is this fixable without a firmware update?