Trunk group operation using LACP
The switch can automatically configure a dynamic LACP trunk group, or you can manually configure a static LACP trunk group.
LACP requires full-duplex (FDx) links of the same media type (10/100Base-T, 100FX, and so on) and the same speed and enforces speed and duplex conformance across a trunk group. For most installations, it is recommended that you leave the port mode settings at
Auto
(the default). LACP also operates with
Auto-10
,
Auto-100
, and
Auto-1000
(if negotiation selects FDx), and
10FDx
,
100FDx
, and
1000FDx
settings.
LACP trunk status commands include:
Trunk display method |
Static LACP trunk |
Dynamic LACP trunk |
---|---|---|
CLI
|
Included in listing. |
Included in listing. |
CLI
|
Included in listing. |
Not included. |
Thus, to display a listing of dynamic LACP trunk ports, you must use the
show lacp
command.
In most cases, trunks configured for LACP on the switches operate as described in the following table.
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 144, depending on how many dynamic and static trunks are currently on the switch. (The switch allows a maximum of 144 trunk groups in any combination of static and dynamic trunks.) Dynamic LACP trunks operate only in the default VLAN (unless GVRP is enabled and
Under the following conditions, the switch automatically establishes a dynamic LACP port trunk group and assigns a port Group name:
Backup Links: A maximum of eight operating links are allowed in the trunk, but, with dynamic LACP, you can configure one or more additional (backup) links that the switch automatically activates if a primary link fails. To configure a link as a standby for an existing eight-port dynamic LACP trunk, ensure that the ports in the standby link are configured as either active-to-active or active-to-passive between switches. Displaying dynamic LACP trunk data: To list the configuration and status for a dynamic LACP trunk, use the CLI
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
|
Static LACP |
Provides a manually configured, static LACP trunk to accommodate these conditions:
Displaying static LACP trunk data : To list the configuration and status for a static LACP trunk, use the CLI
|