Reset Search
 

 

Article

Ports still in active state after GBICs/Clients are removed from x670G2-48x switch

« Go Back

Information

 
TitlePorts still in active state after GBICs/Clients are removed from x670G2-48x switch
Symptoms
  • Traffic stops forwarding on certain ports without any obvious reason.Optics and cable is moved to the other ports and traffic gets restored.
  • The links on the original ports stay in active state even after the optics/cables were removed.
  • No configuration change is done or any physical change (adding new links etc) to the switch.
  • Below is the output from x670G2-48x exhibiting the failure.
    • Ports 2,3,36,37,38 show being in active state (port 1 is in ready state) with no GBICs.
(debug) Summitx670G2-48x.2 # sho port 1-3, 36-38 config
Port Configuration Monitor                              Thu Mar  9 11:09:50 2017
Port     Virtual    Port  Link  Auto   Speed      Duplex   Flow  Load   Media
         router     State State Neg  Cfg Actual Cfg Actual Cntrl Master Pri Red
================================================================================
1        VR-Default  E      R   OFF 10000       FULL                    NONE   
2        VR-Default  E      A   OFF 10000 10000 FULL FULL   NONE        NONE    
3        VR-Default  E      A   OFF 10000 10000 FULL FULL   NONE        NONE    
36       VR-Default  E      A   OFF 10000 10000 FULL FULL   NONE        NONE    
37       VR-Default  E      A   OFF 10000 10000 FULL FULL   NONE        NONE    
38       VR-Default  E      A   OFF 10000 10000 FULL FULL   NONE        NONE    
 
  • Debug hal show optic-info output shows that there is nothing connected on these ports.
Summitx670G2-48x.10 # debug hal show optics-info
Port                       1
No SFP/SFP+ detected.
Port                       2
No SFP/SFP+ detected.
Port                       3
|
|
Port                       36
No SFP/SFP+ detected.
Port                       37
No SFP/SFP+ detected.
Port                       38
No SFP/SFP+ detected.
 
  • From the HW perspective, ports are down:
(debug) Summitx670G2-48x.4 # j h p b s 1 u 0 "ps"
           ena/  speed/ link auto    STP                  lrn  inter   max  loop
      port link  duplex scan neg?   state   pause  discrd ops   face frame  back
       xe0  down  10G FD   SW  No   Forward          None   FA    SFI  1518 
       xe1  down  10G FD   SW  No   Forward          None   FA    SFI  1518
       xe2  down  10G FD   SW  No   Forward          None   FA    SFI  1518
 
      xe35  down  10G FD   SW  No   Forward          None   FA    SFI  1518
      xe36  down  10G FD   SW  No   Forward          None   FA    SFI  1518
      xe37  down  10G FD   SW  No   Forward          None   FA    SFI  1518
 
  • Enabled/disabled ports did not make any difference.
(debug) fm62d-ebr3.fm.intel.com.45 # dis port 2
Port Summary
Port  Display         VLAN Name          Port  Link  Speed  Duplex
#     String          (or # VLANs)       State State Actual Actual
==================================================================
1                     V278-DCEBAR-CS      E     R                           
2                     V278-DCEBAR-CS      D     A     10G   FULL
Environment
  • Summit x670G2-48x
  • EXOS 15.7.2.9
Cause
Debug analysis determine that HW sees the link going down, however this information is not being propagated to the rest of the system. The reason for this is that we break out of the link scan routine due to failure in the MAC reset logic, which is part of the link down process. This failure is due to MAC ports being in ‘hang’ state (not being able to clear their buffers), which explains why the initial failure seen prevented the traffic from being transmitted on these ports.
 

 
Resolution
EXOS 15.7.2.9 (currently running on the switch) contains older SDK. Engineering has confirmed there have been significant enhancements made regarding linkscan logic in newer SDK.
Based on their detailed analysis and findings, SDK version in EXOS 21.1 and above is the recommended EXOS code which has the fixes/enhancements to address the linkscan logic.

NOTE: To date, this issue is only seen on G2 platforms (x670G2-48x to be exact). Pre-G2 platforms use different chipset along with EXOS/SDK version where such errors are not seen.
Additional notes

Feedback

 

Was this article helpful?


   

Feedback

Please tell us how we can make this article more useful.

Characters Remaining: 255