qeth.03aa42 <bus ID of the qeth device>: Interface <interface name> is down because the adjacent port is no longer in reflective relay mode
Explanation
The ISOLATION_FORWARD policy is active for the QDIO data connection isolation
of the qeth device. This policy requires a network adapter in Virtual Ethernet
Port Aggregator (VEPA) mode with an adjacent switch port in reflective relay mode.
The reflective relay mode on the adjacent switch port was disabled. The qeth device
was set offline and the interface was deactivated to prevent any unintended network traffic.
User response
Enable the reflective relay mode again on the adjacent port or use the 'isolation'
sysfs attribute of the qeth device to set a different policy for the QDIO data connection
isolation. You can then resume operations by setting the qeth device back
online and activating the interface.