I am having the same problem (described on this thread Why would Adtran 7100 continuously report "INTERFACE_STATUS.giga-eth 0/1 changed state to testing"?) with my 7100. Except that my interface, has NOTHING connected at it and it is entering in "Test mode".
As well answered on the thread linked, it is caused by a 'MAC address loop'. But, in my case, the loop is being created by the same port that is entering in the testing state, with nothing at all connected to this port.
The mac address table shows that the port has a dynamic entry for it's own mac address. Even if I change the mac address of the port and bring it up, it adds its new own mac address to the table again.
2015.03.31 10:51:42 INTERFACE_STATUS.eth 0/7 changed state to administratively up
2015.03.31 10:51:55 INTERFACE_STATUS.eth 0/7 changed state to up
2015.03.31 10:51:56 INTERFACE_STATUS.eth 0/7 changed state to testing
Again, there is no cable connected to this interface!
port mac address : 00:a0:c8:95:9f:5e
2 00:a0:c8:95:9f:5e DYNAMIC eth 0/7
after changing the mac (to final 7F) it adds it too :
2 00:a0:c8:95:9f:7f DYNAMIC eth 0/7
Could it be a hardware problem?
I have not seen this problem before with the interface changing to testing when no cable is connected. I would recommend opening a support ticket with ADTRAN to have an engineering investigate the hardware on this device.
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