VLAN Port Configuration
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6 Trunks
Trunks allow for the aggregation of multiple full-duplex Ethernet links into a single logical link. Network
devices treat the aggregation as if it were a single link, which increases fault tolerance and provides
load sharing capability.
A trunk interface can be either static or dynamic:
Dynamic—Dynamic trunks use the Link Aggregation Control Protocol (LACP, IEEE standard
802.3ad). An LACP-enabled port automatically detects the presence of other aggregation-capable
network devices in the system and exchanges Link Aggregation Control Protocol Data Units
(LACPDUs) with links in the trunk. The PDUs contain information about each link and enable the
trunk to maintain them.
Static—Static trunks are assigned to a bundle by the administrator. Members do not exchange
LACPDUs. A static trunk does not require a partner system to be able to aggregate its member
ports. This is the default port type.
All members of a trunk must participate in the same protocols. A static trunk interface does not require
a partner system to be able to aggregate its member ports.
From a system perspective, a Trunk is treated as a physical port. A Trunk and a physical port use the
same configuration parameters for administrative enable/disable, port priority, and path cost.
A trunk failure of one or more of the links does not stop traffic in any manner. Upon failure, the flows
mapped to a link are dynamically reassigned to the remaining links of the trunk. Similarly when links
are added to a trunk, existing flows may automatically shift to a different link member within the trunk.
Before any relocation of a conversation, the system ensures reordered frames do not exist.
When ports are added as members to a trunk, they are removed from all existing VLAN memberships
and acquire the membership of trunk VLANs.
The switch supports four trunks, and each trunk can support up to four trunk members.
NOTE:
Trunks are sometimes referred to as link aggregation groups (LAGs) or port-channels.
