Port Trunking
Port Status and Configuration
Table 12-4. LACP Trunk Types
LACP Port Trunk
Configuration
Operation
Dynamic LACP This option automatically establishes an 802.3ad-compliant trunk group, with LACP for the port Type
parameter and DynX for the port Group name, where X is an automatically assigned value from 1 to 6
(2600, 2600-PWR, 4100gl, and 6108) or 1 to 24 (2800), depending on how many dynamic and static trunks
are currently on the switch. (The 2600, 2600-PWR, 4100gl, and 6108 switches allow a maximum of six
trunk groups in any combination of static and dynamic trunks; the 2800 switch allows a maximum of 24
trunk groups in any combination of static and dynamic trunks.)
Under the following conditions, the switch automatically establishes a dynamic LACP port trunk group
and assigns a port Group name:
• The ports on both ends of a link have compatible mode settings (speed and duplex).
• The port on one end of a link must be configured for LACP Active and the port on the other end of
the same link must be configured for either LACP Passive (the default) or LACP Active. For example:
Switch 1
Port X:
LACP Enable: Active
Port Y:
LACP Enable: Active
Switch 2
Port A:
LACP Enable: Active
Port B:
LACP Enable: Passive
Active-to-Active
Active-to-Passive
Either of the above link configurations allow a dynamic LACP trunk link.
Standby Links: A maximum of four (2600, 2600-PWR, 4100gl, and 6108) or eight (2800) operating links
are allowed in the trunk, but, with dynamic LACP, you can configure one or more backup links that the
switch automatically activates if a primary link fails. To configure a link as a standby for an existing
dynamic LACP trunk, ensure that the ports in the standby link are configured the same as either of the
above examples.
Displaying Dynamic LACP Trunk Data: To list the configuration and status for a dynamic LACP trunk,
use the CLI
show lacp command.
Note: The dynamic trunk is automatically created by the switch, and is not listed in the static trunk
listings available in the menu interface or in the CLI show trunk listing.
Static LACP The trunk operates if the trunk group on the opposite device is running one of the following trunking
protocols:
• Active LACP
• Passive LACP
• Trunk
•FEC
This option uses
LACP for the port Type parameter and TrkX for the port Group parameter, where X
is an automatically assigned value from 1 to 6 (2600, 2600-PWR, 4100gl, and 6108) or 1 to 24 (2800),
depending on how many static trunks are currently operating on the switch. (The switch allows the
maximum number of trunk groups in any combination of static and dynamic trunks.)
Displaying Static LACP Trunk Data: To list the configuration and status for a static LACP trunk, use the
CLI
show lacp command. To list a static LACP trunk with its assigned ports, use the CLI show trunk
command or display the menu interface Port/Trunk Settings screen.
Static LACP does not allow standby ports.
12-20