H3C S6850 Series, Руководство по настройке

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When an aggregate interface receives an ARP packet from the management subnet, the device
looks up the sender IP address in the ARP table for a matching entry.
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If no matching entry exists, the device creates an ARP entry on the aggregation member port
from which the packet came in. This mechanism ensures that the returned downlink traffic will
be forwarded out of the member port that received the uplink traffic.
•
If an ARP entry already exists on a different port than the aggregate interface or its member
ports, the device does not update that ARP entry. Instead, the device broadcasts an ARP
request out of all ports to relearn the ARP entry.
When an aggregate interface sends an ARP packet to the management subnet, the device sends
the packet out of all Selected member ports of the aggregate interface.
As shown in Figure 7 , an aggregate link is established between the server and the IRF fabric. The
server sends all uplink traffic of a subnet through Port C1 to Port A1 on the IRF fabric. If that subnet
is not specified as a management subnet, the IRF fabric distributes its downlink traffic across Port A1
and Port B2. To send the downlink traffic of that subnet to the server only through Port A1, you can
specify the subnet as a link aggregation management subnet.
Figure 7 Link aggregation scenario before management subnets are used
Restrictions and guidelines
You can configure a maximum of 20 management subnets.
To ensure correct packet forwarding, delete all ARP entries of a subnet before you specify it as a
management subnet or after you remove it from the management subnet list.
If you are using link aggregation management subnets, do not use the following features:
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DRNI. For more information, see Layer 2—LAN Switching Configuration Guide .
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ARP snooping. For more information, see Layer 3—IP Services Configuration Guide .
Procedure
1. Enter system view.
system-view
2. Specify a link aggregation management subnet.
link-aggregation management-subnet ip-address { mask | mask-length }
By default, no link aggregation management subnets are specified.