the bandwidth aggregation. For example, if there are three Fast Ethernet ports aggregated in a logical port,
then this logical port has bandwidth three times as high as a single Fast Ethernet port has.
The switch supports two kinds of port trunk methods:
LACP:
Ports using Link Aggregation Control Protocol (according to IEEE 802.3ad specification) as their trunk
method can choose their unique LACP GroupID (1~3) to form a logic “trunk port”. The benefit of using
LACP is that a port makes an agreement with its peer port before it becomes a ready member of a “trunk
group” (also called aggregator). LACP is safer than the other trunk method - static trunk.
The switch LACP does not support the followings:
z
Link Aggregation across switches
z
Aggregation with non-IEEE 802.3 MAC link
z
Operating in half-duplex mode
z
Aggregate the ports with different data rates
Static Trunk:
Ports using Static Trunk as their trunk method can choose their unique Static GroupID (also 1~3, this
Static groupID can be the same with another LACP groupID) to form a logic “trunked port”. The benefit of
using Static Trunk method is that a port can immediately become a member of a trunk group without any
handshaking with its peer port. This is also a disadvantage because the peer ports of your static trunk
group may not know that they should be aggregate together to form a “logic trunkd port”. Using Static
Trunk on both end of a link is strongly recommended. Please also note that low speed links will stay in “not
ready” state when using static trunk to aggregate with high speed links.
As to system restrictions, the switch supports maximum 3 trunk groups for LACP and additional 3 trunk groups
for Static Trunk. But in the system capability view, only 3 “real trunked” groups are supported. An LACP trunk
group with more than one ready member-ports is a “real trunked” group. An LACP trunk group with only one or
less than one ready member-ports is not a “real trunked” group. Any Static trunk group is a “real trunked”
group.
Per Trunk Group supports a maximum of 4 ready member-ports. Please note that some decisions will
automatically be made by the system while you are configuring your trunk ports. Trunk Setting Rules are listed
below:
1. Maximum 3 groups are allowed
2. The members of each group cannot exceed more than 4 ports
3. Group 1 and 2 cannot exist member 25 and 26 port
4. Group 3 cannot exist member from 1 to 24 ports
3.13.1 Trunk Port Setting / Status
Port setting/status is used to configure the trunk property of each and every port in the switch system.
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