Default port operation
In the default configuration, LACP is disabled for all ports. If LACP is not configured as Active on at least one end of a link, the port does not try to detect a trunk configuration and operates as a standard, untrunked port. To display this data for a switch, execute the following command in the CLI:
switch# show lacp
Status name |
Meaning |
---|---|
Port Numb |
Shows the physical port number for each port configured for LACP operation (C1, C2, C3 ….) Unlisted port numbers indicate that the missing ports that are assigned to a static trunk group are not configured for any trunking. |
LACP Enabled |
Active: The port automatically sends LACP protocol packets. Passive: The port does not automatically send LACP protocol packets and responds only if it receives LACP protocol packets from the opposite device. A link having either two active LACP ports or one active port and one passive port can perform dynamic LACP trunking. A link having two passive LACP ports does not perform LACP trunking because both ports are waiting for an LACP protocol packet from the opposite device.
NOTE:
In the default switch configuration, LACP is disabled for all ports. |
Trunk Group |
TrkX: This port has been manually configured into a static LACP trunk. Trunk group same as port number: The port is configured for LACP, but is not a member of a port trunk. |
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, Spanning Tree has blocked the port. (The port is not in LACP standby mode.) This may be caused by a (brief) trunk negotiation or a configuration error, such as differing port speeds on the same link or trying to connect the switch to more trunks than it can support.
NOTE:
Standby: The port is configured for dynamic LACP trunking to another device, but the maximum number of ports for the dynamic trunk to that device has already been reached on either the switch or the other device. This port will remain in reserve, or "standby" unless LACP detects that another, active link in the trunk has become disabled, blocked, or down. In this case, LACP automatically assigns a standby port, if available, to replace the failed port.
Some older devices are limited to four ports in a trunk. When eight LACP-enabled ports are connected to one of these older devices, four ports connect, but the other four ports are blocked. |
LACP Partner |
Yes: LACP is enabled on both ends of the link. No: LACP is enabled on the switch, but either LACP is not enabled or the link 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 is 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. |