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Cisco Bug: CSCum75740 - 1500-byte packets with df-bit set are dropped on a PE

Last Modified

Jun 12, 2018

Products (6)

  • Cisco IOS
  • Cisco Catalyst 6500 Series Virtual Switching Supervisor Engine 720 with 10GE uplinks
  • Cisco ME 6524-GS Ethernet Switch
  • Cisco Catalyst 6500 Series Supervisor Engine 32 / MSFC2A
  • Cisco ME 6524-GT Ethernet Switch
  • Cisco Catalyst 6500 Series Supervisor Engine 720 / MSFC3

Known Affected Releases


Description (partial)

PE drops incoming packets received on a PE-CE interface if the size is greater than 1493 bytes.
At the time, PE returns ICMP error complaining fragmentation is required.

The problem is seen when the following conditions are met.
 -The packet is routed to a single hop MPLS-TE tunnel.
 -The packet is process-switched for some reason.
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Bug Details Include

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