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Cisco Bug: CSCvu57704 - Auto detect the problem if the latency and traffic test is not performed correctly on the ISL link

Last Modified

Jun 22, 2020

Products (1)

  • Cisco MDS 9000 Series Multilayer Switches

Known Affected Releases

8.4(1a)

Description (partial)

Symptom:
The latency test and traffic tests are two separate tests to check the quality of the ISL link. If the latency test is configured and if we run traffic generator on the other side, MDS says the test has failed, but does not give the right reasons. 

Example:

On one side of the ISL link
switch1# diagnostic isl reflector latency_test loop-back interface fc1/9 enable 

On the other side of the ISL link,

switch2# diagnostic isl generator int fc1/9 start duration 11 frame_size min 16 max 517 step 1 link_speed 8G 
Waiting for sync to be achieved on the link ....
Link initialized successfully. Starting the test.
Please use show diagnostic isl result interface fc1/9 after 11 seconds to check the result
switch2# show diagnostic isl result interface fc1/9

---------------------------------------------------------
Single hop  Traffic test Result for port: fc1/9
Packets Transmitted:                             98317
Packets Recieved:                                90603
ISL traffic Efficiency (percent):                92.1540
---------------------------------------------------------
ISL Diag Test has failed
Execute CLI < show diagnostic isl internal errors > to know the reasons for failure
---------------------------------------------------------
switch2#  show diagnostic isl internal errors
3) Event:E_DEBUG, length:157, at 172586 usecs after Thu Mar 26 13:58:56 2020
    [1734437220] _isl_diag_traffic_test_timer_cb(185): Test completed with errors:if_index:0x1008
000 status:0 test:1 in_disc:0x2e6 out_disc:0x1cb4 bad_words:0x828d4

Conditions:
The test has to be performed by enabling latency test reflector on one side of the ISL link and run diagnostic isl generator on the other side of the ISL.

Example:

On one side of the ISL link
switch1# diagnostic isl reflector latency_test loop-back interface fc1/9 enable

On the other side of the ISL link,

switch2# diagnostic isl generator int fc1/9 start duration 11 frame_size min 16 max 517 step 1 link_speed 8G 
Waiting for sync to be achieved on the link ....
Link initialized successfully. Starting the test.
Please use show diagnostic isl result interface fc1/9 after 11 seconds to check the result
switch2# show diagnostic isl result interface fc1/9

---------------------------------------------------------
Single hop  Traffic test Result for port: fc1/9
Packets Transmitted:                             98317
Packets Recieved:                                90603
ISL traffic Efficiency (percent):                92.1540
---------------------------------------------------------
ISL Diag Test has failed
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