Dell Force10 E300, Configuration Manual

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574 | Layer 2
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To ensure that existing network applications see no difference when a primary interface in a redundant pair
transitions to the backup interface, be sure to apply
identical configurations of other traffic parameters to
each interface.
If you remove an interface in a redundant link (remove the line card of a physical interface or delete a port
channel with the
no interface port-channel
command), the redundant pair configuration is also removed.
Important Points about Configuring Redundant Pairs
• An interface cannot be used as a backup for more than one interface; an interface can have no more
than one backup. A backup interface cannot have a backup interface.
• The active and standby/backup interfaces do not have to be of the same type (1G, 10G, etc).
• You may not enable any Layer 2 protocol on an interface in a redundant pair or on a port connected to
a redundant interface.
• If the active interface in a redundant pair fails, you may have to synchronize the MAC addresses stored
in the MAC and ARP tables to ensure that the backup interface can access the same MAC addresses
that were learned on the failed active interface. To do so, enter the
mac-address-table station-move
refresh-arp
command (global configuration mode).
• When you use a static or dynamic port channel as the active or backup interface in a redundant pair, the
following conditions apply:
• If you use two port-channel interfaces with different configurations in a redundant pair, traffic is
transmitted in the same way following a transition to the backup interface. There is no difference
in performance. For example, two port channels in a redundant pair can contain a different number
and type of member ports or use different LACP modes.
• There are no requirements on the number or type of links in a port channel.
• There are no requirements on the location of the member links in a port channel, such as on the
same line card or stacked device.
• If you use a dynamic port channel in a redundant pair, LACP operation on the port channel is not
affected by its status as the active or backup interface.
• If you manually shut down a port channel that is the active interface in a redundant pair (
shutdown
command), the status of the port channel transitions to DOWN and the backup interface becomes
active.
• If the number of member links with an “oper up” status is less than the minimum number of
required links configured for a port channel that is the active interface in a redundant pair, the
status of the port channel transitions to DOWN and the backup interface becomes active.
• If a static or dynamic port channel is used in a redundant pair, the port channel cannot be used as a
member of a failover group in shared LAG state tracking (see in LACP chapter).
• A dynamic port channel that is used in a redundant pair can participate in hitless LACP (see
Configure LACP as Hitless in LACP chapter).