This read-write INTEGER, one of disabled(1), operating(2), or linkfail(3), starts or stops the IMA test-pattern procedure and reports whether at least one link failed the test; only disabled and operating may be written, with linkfail persisting until either disabled is set or no link instance still reports failure. An administrator sets operating(2) to run the loopback test and watches for the status to change to linkfail(3), flagging a specific bonded link as suspect. For example, seeing this value change to linkfail(3) after starting the test tells the operator at least one link in the IMA group failed the test pattern check and needs further investigation.