3Com S7906E - Switch, Configuration Manual

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For an S7900E series Ethernet switch in an IRF, its 100-Mbps, GE and 10GE ports are numbered in the
format of interface type A/B/C/D ; for an S7900E series Ethernet switch not in any IRF, its 100-Mbps,
GE and 10GE ports are numbered in the format of interface type B/C/D .
z
A: Number of the switch in an IRF;
z
B: Slot number of the card in the switch;
z
C: Sub-slot number on a card;
z
D: Number of a port on a card.
If the switch uses LSQ1SRP2XB or LSQ1SRP12GB SRPUs, it simulates two virtual LPU slots with the
slot numbers following the largest slot number. The virtual LPUs correspond to the SRPUs, and the
Ethernet ports on the virtual LPUs correspond to the Ethernet ports on the SRPUs and the numbering
rules for the ports are the same as those described earlier. If you want to configure the Ethernet ports on
the SRPUs, you need to configure on the virtual LPUs
For more information about SFP and XFP ports involved in this chapter, see 3Com S7900E Family
Getting Started Guide .
Configuring Flow Control on Port
When flow control is enabled on both sides, if traffic congestion occurs at the ingress port, it will send a
Pause frame notifying the egress port to temporarily suspend the sending of packets. The egress port is
expected to stop sending any new packet when it receives the Pause frame. In this way, flow control
helps to avoid dropping of packets. Note that this will be possible only after flow control is enabled on
both the ingress and egress ports.
Follow these steps to enable flow control on a port:
To do… Use the command… Remarks
Enter system view system-view —
Enter Ethernet port or OLT port
view interface interface-type
interface-number
—
Enable flow control flow-control
Required
By default, receive flow control
is disabled on a port.
Configuring the Suppression Time of Physical-Link-State Change on an Ethernet
Port
An Ethernet port operates in one of the two physical link states: up or down. During the
physical-link-state change suppression time, the physical-link-state changes of ports will not be
propagated to the system. Only after the suppression time has elapsed will the system be notified of the
physical-link-state changes by the physical layer. This functionality reduces the extra overhead
occurred due to frequent physical-link-state changes within a short period of time.
Follow these steps to configure the suppression time of physical-link-down-state changes on a port: