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

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Loopback and clock slave cannot be set at the same time. Otherwise, POS interfaces cannot be
connected successfully.
Examples
# Enable internal loopback on POS 1/0.
<Sysname> system-view
[Sysname] interface pos 1/0
[Sysname-Pos1/0] loopback local
mtu
Use mtu to set the MTU size of a POS interface.
Use undo mtu to restore the default.
Syntax
mtu size
undo mtu
Views
POS interface view
Default command level
2: System level
Parameters
size: Specifies the size of the maximum transmission unit (MTU) in the range of 128 to 1650 bytes.
Usage guidelines
The MTU setting affects the assembly and fragmentation of IP packets.
In QoS, the length of queues is limited. If the MTU of the interface is too small, a large packet might be
fragmented into so many fragments that the queue cannot hold them and discard them. To avoid this
situation, extend the queue length by using the qos fifo queue-length command in interface view. The
default queuing mechanism on the interface is FIFO. For more information about queuing configuration,
see ACL and QoS Configuration Guide.
Examples
# Set the MTU of POS 1/0 to 1492.
<Sysname> system-view
[Sysname] interface pos 1/0
[Sysname-Pos1/0] mtu 1492
Related commands
display interface pos
reset counters interface
Use reset counters interface to clear POS interface statistics.
Syntax
reset counters interface [ pos [ interface-number ] ]