R2511-HP MSR Router Series Interface Command Reference(V5)

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--- Serial1/0/0 looptest statistics ---
5 packet(s) transmitted
5 packet(s) received
0 packet(s) lost
0 packet(s) error
0.00% packet lost
0.00% packet error
round-trip min/avg/max = 1/1/1 ms
conclusion: loopback
Related commands
• fe1 loopback
• ft1 loopback
• loopback
mtu
Use mtu to set the MTU for an interface.
Use undo mtu to restore the default.
Syntax
mtu size
undo mtu
Default
The MTU of an interface is 1500 bytes.
Views
Serial interface view, AUX interface view, AM interface view, Cellular interface view, E1-F interface view,
T1-F interface view
Default command level
2: System level
Parameters
size: Maximum transmission unit (MTU) in bytes, in the range of 128 to 1500 bytes.
Usage guidelines
Due to the length of QoS queue, a packet might be discarded if the MTU is relatively small and the
packet is segmented into too many fragments. To avoid this situation, you can increase the QoS queue
length by using the qos fifo queue-length command in interface view. For more information, see ACL and
QoS Configuration Guide.
The MTU setting can affect IP packets assembly and fragmentation on the interface.
When you use the mtu command on a WAN interface, execute the shutdown command, and then the
undo shutdown command to make your configuration take effect.
Examples
# Set the MTU of interface Serial 2/0 to 1200 bytes.
<Sysname> system-view