The clear ip df command enables a device to forcibly fragment IP packets on an outbound interface.
The undo clear ip df command disables a device from forcibly fragmenting IP packets on an outbound interface.
By default, a device is disabled from forcibly fragmenting IP packets on an outbound interface is disabled.
100GE interface view, 10GE interface view, 25GE interface view, 400GE interface view, 40GE interface view, 50GE interface view, Eth-Trunk interface view, FlexE sub-interface view, FlexE interface view, GE optical interface view, GE interface view, GE electrical interface view, GMPLS-UNI interface view, Global VE sub-interface view, Global VE interface view, Loopback interface view, Tunnel interface view, VBDIF interface view, VE sub-interface view, VE interface view, VLANIF interface view, Sub-interface view, Management interface view, Virtual template view
Usage Scenario
An IP header contains a Don't Fragment (DF) field, indicating whether an IP packet can be fragmented. If the DF field of an IP packet is set to 1, a device does not fragment the packet. If the size of an IP packet is greater than the MTU of an interface because of a protocol encapsulation, a device discards the packet and sends ICMP error messages, causing data loss. To prevent data loss in this scenario, run the clear ip df command to enable the forced fragmentation of IP packets.
Configuration Impact
If the function is enabled, the system resets the DF field to 0 and performs fragmentation when the IP packet meets the following requirements:
Precautions
This command takes effect only for the IP packets sent by the CPU, but not for the packets forwarded by the CPU.