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Cisco Bug: CSCur05027 - Loopback error occurs when keepalive packet is looped back to the port.

Last Modified

Nov 27, 2020

Products (35)

  • Cisco Catalyst 2960-X Series Switches
  • Cisco Catalyst 2960X-48LPS-L Switch
  • Cisco Catalyst 2960X-24PD-L Switch
  • Cisco Catalyst 2960X-24PS-L Switch
  • Cisco Catalyst 2960S-24PD-L Switch
  • Cisco Catalyst 2960XR-48FPS-I Switch
  • Cisco Catalyst 2960XR-24TD-I Switch
  • Cisco Catalyst 2960X-48TD-L Switch
  • Cisco Catalyst 2960X-24TS-LL Switch
  • Cisco Catalyst 2960S-48LPS-L Switch
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Known Affected Releases

15.0(2)EX 15.0(2)EX1

Description (partial)

Loopback error occurs when keepalive packet is looped back to the uplink port.The following error is detected on ten GigabitEthernet SFP ports with fiber SFP:


By default, the loopback and keepalives should be disabled on fiber and cooper uplink ports. This issue impacts Catalyst 2960X and 6800IA platforms.
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