3Com 2226 PLUS - Manual (Page 54)

54 C HAPTER 4: C ONFIGURING THE S WITCH
CAUTION: Before manually setting a port to
full-duplex, verify that the device connected to the port
is also manually set to the same speed and duplex
setting. If connecting link partners are left to
autonegotiate for a link manually set on this switch to
full-duplex, they will always negotiate to half-duplex,
resulting in a duplex mismatch. This can result in a
significant reduction in network performance. If you are
unsure of how to configure the speed/duplex setting,
simply enable autonegotiation for the port.
You cannot modify the speed/duplex settings of ports
that are members of a trunk or aggregated link.
Supported SFP transceivers only operate at 1000 Mbps
full-duplex. Inserting an SFP transceiver into a gigabit
port disables the corresponding RJ-45 port, even if no
fiber cable is inserted.
Link Aggregation
Link aggregation, also called “trunking”, refers to
bonding multiple ports into a single group to effectively
combine the bandwidth into a single connection or a
“trunk”. If you are connecting the Switch to another
switch or to an Internet backbone, you can aggregate
links on the Switch to increase throughput and prevent
packet loopback between switches.
For link aggregation to work, the trunks must be
configured on both ends (switches).
Guidelines for Creating Trunks
■ Any port on the Switch can be used for creating a
trunk.
■ This switch supports a maximum of four trunks.
■ Each trunk may contain up to four members.
■ A port may only be a member of one trunk at any
one time.
■ All ports in a trunk must be configured in an
identical manner, including communication mode
(that is, speed, duplex mode and flow control).