Vlans and lags, Lag thresholds, Port channels – Dell POWEREDGE M1000E User Manual

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Port Channel Commands

A LAG can be either static or dynamic not both. It cannot have some

members participate in the protocol while other members not participate.

Additionally, it is not possible to change a LAG from static to dynamic via the

CLI. You must remove the member ports from the static LAG and then add

them to the dynamic LAG.

VLANs and LAGs

When members are added to a LAG, they are removed from all existing

VLAN membership. When members are removed from a LAG, the members

rejoin the VLANs that they were previously members of as per the

configuration file.
The LAG interface can be a member of a VLAN complying with IEEE

802.1Q.

LAG Thresholds

In many implementations, a LAG is declared as up if any one of its member

ports is active. This enhancement provides configurability for the minimum

number of member links to be active to declare a LAG up. Network

administrators can also utilize this feature to automatically declare a LAG

down when only some of the links have failed.

Port Channels

Trunking, which is also called Port Channels or Link Aggregation, is initiated

and maintained by the periodic exchanges of Link Aggregation Control PDUs

(LACPDUs). When LACP is enabled for a physical interface, LACPDUs

must not be dropped for any reason. Conversely, when LACP is disabled for

the physical interface LACPDUs must be dropped.
From a system perspective, a LAG is treated as a physical port. A LAG and a

physical port use the same configuration parameters for administrative

enable/disable, port priority, and path cost. When a physical port is

configured as part of a LAG, it no longer participates in forwarding operations

until the LAG becomes active.

2CSPC4.XModular-SWUM200.book Page 574 Thursday, March 10, 2011 11:18 AM

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