R3303-HP HSR6800 Routers Interface Command Reference

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Syntax
mtu size
undo mtu
Default
The MTU of an Ethernet interface or subinterface is 1500 bytes.
Views
Layer 3 Ethernet interface view, Layer 3 Ethernet subinterface view
Default command level
2: System level
Parameters
size: Specifies an MTU value. The value range is 46 to 9600 bytes. The maximum MTU configurable on
an interface might be lower than 9600 bytes depending on the device model, interface module model,
and interface type.
Usage guidelines
As the size of MTU decreases, the number of fragments grows. When setting MTU for an interface, you
should consider QoS queue lengths (for example, the default FIFO queue length is 75) to avoid a too
small MTU causing packet drop in QoS queuing. To achieve the best result, you can tune MTU with the
mtu command or QoS queue lengths with the qos fifo queue-length command. For more information,
see ACL and QoS Command Reference.
Examples
# Set the MTU to 1430 bytes for the Layer 3 Ethernet interface GigabitEthernet 4/0/5.
<Sysname> system-view
[Sysname] interface gigabitethernet 4/0/5
[Sysname-GigabitEthernet4/0/5] mtu 1430
# Set the MTU to 1400 bytes for the Layer 3 Ethernet subinterface GigabitEthernet 4/0/5.1.
<Sysname> system-view
[Sysname] interface gigabitethernet 4/0/5.1
[Sysname-GigabitEthernet4/0/5.1] mtu 1400
promiscuous
Use promiscuous to configure a Layer 3 Ethernet interface to operate in promiscuous mode.
Use undo promiscuous to cancel the promiscuous operating mode.
Syntax
promiscuous
undo promiscuous
Default
A Layer 3 Ethernet interface does not operate in promiscuous mode.
Views
Layer 3 Ethernet interface view