Command Line Reference Guide

IPv4 Routing | 623
ip max-frag-count
c e s
Set the maximum number of fragments allowed in one packet for packet re-assembly.
Syntax
ip max-frag-count count
To place no limit on the number of fragments allowed, enter no ip max-frag-count.
Parameters
Defaults
No limit is set on number of fragments allowed.
Command Modes
CONFIGURATION
Command
History
Usage
Information
To avoid Denial of Service (DOS) attacks, keep the number of fragments allowed for re-assembly low.
ip mtu
e
Set the IP MTU (frame size) of the packet transmitted by the RPM for the line card interface. If the
packet must be fragmented, FTOS sets the size of the fragmented packets to the size specified in this
command.
Syntax
ip mtu value
To return to the default IP MTU value, enter no ip mtu.
Parameters
Defaults
1500 bytes
Command Modes
INTERFACE (Gigabit Ethernet and 10 Gigabit Ethernet interfaces)
Command
History
Usage
Information
When you enter no mtu command, FTOS reduces the ip mtu value to 1536 bytes. To return the IP
MTU value to the default, enter no ip mtu.
You must compensate for Layer 2 header when configuring link MTU on an Ethernet interface or
FTOS may not fragment packets. If the packet includes a Layer 2 header, the difference between the
link MTU and IP MTU (ip mtu command) must be enough bytes to include for the Layer 2 header.
count
Enter a number for the number of fragments allowed for re-assembly.
Range: 2 to 256
Version 8.1.1.0 Introduced on E-Series ExaScale
Version 7.6.1.0 Added support for S-Series
Version 7.5.1.0 Added support for C-Series
pre-Version 6.1.1.0 Introduced for E-Series
value
Enter the maximum MTU size if the IP packet is fragmented.
Default: 1500 bytes
Range: 576 to 9234
Version 8.1.1.0 Introduced on E-Series ExaScale
pre-Version 6.1.1.0 Introduced for E-Series