Optimizing Port Usage Through Traffic Control and

Optimizing Port Usage Through Traffic Control and Port Trunking

Port Trunking

Status Name Meaning

Port Status Up: The port has an active LACP link and is not blocked or in Standby mode.

Down: The port is enabled, but an LACP link is not established. This can indicate, for example, a port that is not connected to the network or a speed mismatch between a pair of linked ports.

Disabled: The port cannot carry traffic.

Blocked: LACP, STP, or FEC has blocked the port. (The port is not in LACP Standby mode.) This may be due to a trunk negotiation (very brief) or a configuration error such as differing port speeds on the same link or attempting to connect the Switch 2512/2524 to more than one trunk.

Standby: The port is configured for dynamic LACP trunking, but the maximum number of ports for the Dyn1 trunk has already been reached on either the Switch 2512/2524 or the device on the other end of the trunked links. This port will remain in reserve, or “standby” unless LACP detects another, active link in the trunk becomes disabled, blocked, or down. In this case, LACP automatically assigns a Standby port, if available, to replace the failed port.

LACP Partner Yes: LACP is enabled on both ends of the link.

No: LACP is enabled on the Switch 2512/2524, but is not enabled, or LACP has not been detected on the opposite device.

LACP Status Success: LACP is enabled on the port, detects and synchronizes with a device on the other end of the link, and can move traffic across the link.

Failure: LACP is enabled on a port and detects a device on the other end of the link, but is not able to synchronize with this device, and therefore not able to send LACP packets across the link. This can be caused, for example, by an intervening device on the link (such as a hub), a bad hardware connection, or if the LACP operation on the opposite device does not comply with the IEEE 802.3ad standard.

LACP Notes and Restrictions

Changing Trunking Methods. The switch supports one trunk group. Thus, a port belonging to an LACP dynamic trunk (Dyn1) cannot be configured as a member of a static trunk (Trk1) without first eliminating the dynamic trunk. Also, to convert a trunk from static to dynamic, you must first eliminate the static trunk.

Static LACP Trunks. Where a port is configured for LACP (Active or Passive), but does not belong to an existing trunk group, you can add that port to a static trunk. Doing so disables dynamic LACP on that port, which means you must manually configure both ends of the trunk.

VLANs and Dynamic LACP. A dynamic LACP trunk operates only in the default VLAN unless you have enabled GVRP on the switch. If you want to use LACP for a trunk on a non-default VLANand GVRP is disabled, configure the trunk as a static trunk.

STP and IGMP. If spanning tree (STP) and/or IGMP is enabled in the switch, a dynamic LACP trunk operates only with the default settings for these features and does not appear in the port listings for these features.

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