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Cisco Bug: CSCsz50538 - Fragmentation stops working for packet size > Tun MTU in DMVPN+NAT-T

Last Modified

Jan 30, 2017

Products (1)

  • Cisco IOS

Known Affected Releases

12.4(15)T9 12.4(9)T7

Description (partial)


Packets needing to be fragmented to pass through DMVPN tunnel might be dropped silently.


This defect has been seen on 1801 routers running software version 12.4(9)T and 12.4(15)T.
The tunnel must be configured for DMVPN encapsulating MPLS. The traffic to be encrypted must be injected in the router via a VRF different from the global VRF.
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