R3303-HP 6600/HSR6600 Routers Layer 2 - WAN Command Reference Guide

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Syntax
mtu mtu-number
undo mtu
Default
The MTU for ATM interfaces is 1500 bytes.
Views
ATM interface view
Default command level
2: System level
Parameters
mtu-number: Specifies the MTU size on an ATM interface in bytes. The value range for this argument is
128 to 2000 except for HIM-AL1P and HIM-AL2P cards installed in HSR6602 routers or in 6604, 6608,
or 6616 routers with MCP as the MPU. The value range is 128 to 9600 for these HIM-AL1P and HIM-AL2P
cards.
Usage guidelines
The MTU only influences the packet assembly and disassembly at the IP layer at the ATM interface. Due
to the limit of QoS queue length, too small an MTU causes numerous fragments. Thus, some fragments
might be dropped by the QoS queue. The length of the QoS queue can be increased appropriately. The
default queue dispatching mechanism used by PVC is FIFO. You can use the qos fifo queue-length
command in the PVC view to change its queue length.
This command applies to ATM main interface and subinterface simultaneously.
Examples
# Set the MTU to 1492 bytes for interface ATM 1/0/1.
<Sysname> system-view
[Sysname] interface atm 1/0/1
[Sysname-Atm1/0/1] mtu 1492
oam ais-rdi
Use oam ais-rdi to set the parameters related to AIS/RDI alarm cell detection.
Use undo oam ais-rdi to restore the default.
Syntax
oam ais-rdi up up-seconds down down-count
undo oam ais-rdi
Default
A PVC goes down when an AIS/RDI alarm cell is received and goes up if no AIS/RDI alarm cells are
received in the last 3 seconds.
Views
PVC view, ATM class view