Mtu (Ppp) - Allied Telesis AR2050V Command Reference Manual

PPP C
OMMANDS
(PPP)
MTU

mtu (PPP)

Overview Use this command to set the Maximum Transmission Unit (MTU) size for a PPP
interface, where MTU is the maximum packet size that PPP interfaces can transmit.
Use the no variant of this command to remove a previously specified MTU size for
a PPP interface, and restore the default MTU size (1492 bytes) for PPP interfaces.
Syntax mtu <mtu-size>
no mtu
NOTE
Default The default MTU size is 1492 bytes for PPPoE interfaces. The MTU should be greater
than, or equal to, the MSS.
Mode Interface Configuration for PPP interfaces.
Usage If a router receives an IPv4 packet for another PPP interface with an MTU size
smaller than the packet size, and if the packet has the ' don't fragment' bit set,
then the switch will send an ICMP ' destination unreachable' (3) packet type and
a ' fragmentation needed and DF set' (4) code back to the source.
See the
first setting the MTU size.
Examples To configure an MTU size of 1492 bytes on PPP interface ppp0, use the commands:
awplus#
awplus(config)#
awplus(config-if)#
To restore the MTU size to the default MTU size of 1492 bytes on PPP interface
ppp0, use the commands
awplus#
awplus(config)#
awplus(config-if)#
Related ip tcp adjust-mss
Commands
show interface (PPP)
C613-50186-01 Rev B
Parameter Description
<mtu-size>
<68-1492> Specifies the Maximum Transmission Unit (MTU) size in
bytes, where 1492 bytes is the default MTU size for a PPPoE interface
and 1500 bytes for PPP via other lower layer interface types. This
allows for the 8-byte PPPoE header that is added to make up the total
of a 1582 byte packet that matches the default MTU size for the
Ethernet link..
: For PPPoE the minimum MTU value is 128.
ip tcp adjust-mss
configure terminal
interface ppp0
configure terminal
interface ppp0
Command Reference for AR2050V
AlliedWare Plus™ Operating System - Version 5.4.7-1.x
command to set the Maximum Segment Size (MSS) after
mtu 1492
no mtu
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