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Cisco Bug: CSCuo80849 - MDS 9710 DS-X9448-768K9 Port Loopback test failed

Last Modified

Jan 25, 2019

Products (1)

  • Cisco MDS 9000 Series Multilayer Switches

Known Affected Releases


Description (partial)

Some ports may fail a loopback test and put ports in that port group into a hwfailure state.

The error message seen on the console or syslog output would appear as follows:

%DIAG_PORT_LB-2-INT_PORT_LOOPBACK_TEST_FAIL: Module:2 Test:Internal PortLoopback failed 10 consecutive times. Faulty module: affected ports:affected ports:9-16  Error:Loopback test failed. Packets possibly lost on the switch fabric

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