After upgrading to SLXOS 20.1.1 or higher, the starting MAC address of the system is modified by two digits.
The MAC address modification may cause issues if there are permit or deny ACL’s using the MAC address of the device, specifically when a peer is expecting the prior MAC address (from 18r.x software version), and a different MAC address is now seen (with 20.x.x software version).
SLXOS 20.1.1 or higher
Network administrators may be required to reconfigure ALCs on the remote peer side to account for the modified MAC addresses, which are modified by two digits.
The full field notice can be found here: https://extremeportal.force.com/ExtrArticleDetail?an=000094730
Contact Us:Sam PirokCommunity@extremenetworks.com