Cisco ASA 5505 - Manual (Page 247)

6-5
Cisco ASA 5500 Series Configuration Guide using the CLI
Chapter 6 Starting Interface Configuration (ASA 5510 and Higher)
Information About Starting ASA 5510 and Higher Interface Configuration
EtherChannels
An 802.3ad EtherChannel is a logical interface (called a port-channel interface) consisting of a bundle
of individual Ethernet links (a channel group) so that you increase the bandwidth for a single network.
A port channel interface is used in the same way as a physical interface when you configure
interface-related features.
You can configure up to 48 EtherChannels.
This section includes the following topics:
• Channel Group Interfaces, page 6-5
• Connecting to an EtherChannel on Another Device, page 6-5
• Link Aggregation Control Protocol, page 6-6
• Load Balancing, page 6-7
• EtherChannel MAC Address, page 6-7
Channel Group Interfaces
Each channel group can have eight active interfaces. Note that you can assign up to 16 interfaces to a
channel group. While only eight interfaces can be active, the remaining interfaces can act as standby
links in case of interface failure.
All interfaces in the channel group must be the same type and speed. The first interface added to the
channel group determines the correct type and speed.
The EtherChannel aggregates the traffic across all the available active interfaces in the channel. The port
is selected using a proprietary hash algorithm, based on source or destination MAC addresses, IP
addresses, TCP and UDP port numbers and vlan numbers.
Connecting to an EtherChannel on Another Device
The device to which you connect the ASA EtherChannel must also support 802.3ad EtherChannels; for
example, you can connect to the Catalyst 6500 switch.
When the switch is part of a Virtual Switching System (VSS), then you can connect ASA interfaces
within the same EtherChannel to separate switches in the VSS. The switch interfaces are members of the
same EtherChannel port-channel interface, because the separate switches act like a single switch (see
Figure 6-1 ).