Link Aggregation Commands
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Guidelines for Creating Trunks
General Guidelines –
Finish configuring port trunks before you connect the corresponding network
cables between switches to avoid creating a loop.
A trunk can have up to eight ports.
The ports at both ends of a connection must be configured as trunk ports.
All ports in a trunk must be configured in an identical manner, including
communication mode (i.e., speed, duplex mode and flow control), VLAN
assignments, and CoS settings.
Any of the Gigabit ports on the front panel can be trunked together, including
ports of different media types.
All the ports in a trunk have to be treated as a whole when moved from/to,
added or deleted from a VLAN via the specified port-channel.
STP, VLAN, and IGMP settings can only be made for the entire trunk via the
specified port-channel.
Dynamically Creating a Port Channel –
Ports assigned to a common port channel must meet the following criteria:
Ports must have the same LACP system priority.
Ports must have the same port admin key (Ethernet Interface).
If the port channel admin key (lacp admin key - Port Channel) is n ot set when
a channel group is formed (i.e., it has the null value of 0), this ke y is set to the
same value as the port admin key (lacp admin key - Ethernet Interface) used
by the interfaces that joined the group.
However, if the port channel admin key is set, then the port admin key must
be set to the same value for a port to be allowed to join a channel group.
If a link goes down, LACP port priority is used to select the backup link.
channel-group
This command adds a port to a trunk. Use the no form to remove a port from a trunk.
Syntax
channel-group channel-id
no channel-group
channel-id - Trunk index (Range: 1-4)
Default Setting
The current port will be added to this trunk.
Command Mode
Interface Configuration (Ethernet)