Catalyst 9800 on Hyper v issue

[guidov2]

Hello,

Strange issue with Catalyst 9800 hosted on Hyper v:

Interfaces doesn't work in switch port mode:

if interfaces are configured in switchport mode (access or trunk) it seem there is no transmission to the outside.

In routing mode it works correctly.

Already installed on other VM (not Hyper v) without issue.

from WLC we can see the arp table is populated .. but other devices cannot see its mac address and there is no entry in apr table.

with FIA packet trace we can see  

Drop with reason 493.

in attach screenshot of packet capture

[jonathga94]

To revive this topic, the Hyper-V deployment of the WLC 9800-CL requires configuring vNIC as trunk and enabling MAC address spoofing on Hyper-V. Without MAC address spoofing, the WLC has a hard time adding a MAC address on the L2 header, resulting in failed packet transmission. The guide below provides instructions on how to configure MAC address spoofing on Hyper-V:

https://www.cisco.com/c/en/us/td/docs/wireless/controller/9800/9800-cloud/installation/b-c9800-cl-install-guide/b-c9800-cl-install-guide_chapter_01011.html

[shrikant-kshirsagar]

Enabling MAC address spoofing on Hyper-V for vNIC solved issue for me as well.