Trunking Configuration - Waters Network Systems ProSwitch 2800M Operating Manual

5.16

Trunking Configuration

The Port Trunking Configuration is used to configure the settings of Link Aggregation. More than
one port can be bundled with the same speed, full duplex and the same MAC to be a single
logical port. The logical port aggregates the bandwidth of these ports. This means you can
apply your current Ethernet equipment to build 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.
The switch supports two types of port trunking methods:
LACP:
Ports using Link Aggregation Control Protocol (according to IEEE 802.3ad specification) as their
trunking method can choose their unique LACP GroupID (1~8) to form a logic trunked 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 trunking method - static trunk.
The switch LACP does not support the following:

Link Aggregation across switches

Aggregation with non-IEEE 802.3 MAC link

Operating in half-duplex mode

Aggregate the ports with different data rates
Static Trunk:
Ports using Static Trunk as their trunk method can choose their unique Static Group ID (also
1~3, this Static group ID can be the same with another LACP group ID) to form a logic trunked
port. The benefit of the using Static Trunk method is that a port can immediately become a
member of a trunk group without handshaking with its peer port. This is a disadvantage
because the peer ports of the static trunk group may not know that they should aggregate
together to form a logical trunked port. Using Static Trunk on both ends of a link is strongly
recommended. Low speed links will stay in not ready state when using static trunk to
aggregate with high speed links.
The switch supports a maximum of three trunk groups for LACP and additional three trunk
groups for Static Trunk. In the system capability view, only three "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 Trunking Group supports a maximum of four ready member-ports. Please note that some
decisions will automatically be made by the system while you are configuring your trunking ports.
Some configuration examples are listed below:
 Rule 1 – Maximum of three groups are allowed.
 Rule 2 - The members of each group cannot exceed more than four ports.
 Rule 3 – Group 1 and 2 cannot have as members ports 25 and 26.
 Rule 4 – Group 3 cannot have members from 1 to 24 ports.
Waters Network Systems 2800M/MR User's Manual Page 75