Network Administration 4-17

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If you want changes made with ifconfig to remain in effect after a reboot, include
the ifconfig commands in the /etc/rc file.

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Table 4-7 illustrates examples of how to use the ifconfig command to view inter-
face configuration information.
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To get the security of failover or the throughput that multiple interfaces working as
one interface can provide, you can group up to four Ethernet interfaces. You group
them into a logical interface unit known as a trunk. A trunk is composed of links, each
of which is an interface. Commands that work on physical interfaces also work on
trunks, except that the ifstat command returns limited trunk information.

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Trunks are also referred to by the following terms:
Virtual aggregations
Link aggregations
EtherChannel virtual interfaces.
This document uses the term trunk.

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Figure 4-1 shows four separate interfaces, e3a, e3b, e3c, and e3d, before trunking.

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Show the current configurations of all
network interfaces.
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Show the current configuration of a
specific network interface.
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Example: Enter the following com-
mand to show the current
configuration of interface e0:
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