VigorSwitch G2240 User’s Guide
106
2
2
.
.
1
1
1
1
T
T
r
r
u
u
n
n
k
k
i
i
n
n
g
g
C
C
o
o
n
n
f
f
i
i
g
g
u
u
r
r
a
a
t
t
i
i
o
o
n
n
The Port Trunking Configuration is used to configure the settings of Link Aggregation.
You can bundle more than one port with the same speed, full duplex and the same MAC to
be a single logical port, thus the logical port aggregates the bandwidth of these ports. This
means you can apply your current Ethernet equipments 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 has.
The switch supports two kinds of port trunking methods:
L
L
A
A
C
C
P
P
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 followings:
¾
Link Aggregation across switches
¾
Aggregation with non-IEEE 802.3 MAC link
¾
Operating in half-duplex mode
¾
Aggregate the ports with different data rates
S
S
t
t
a
a
t
t
i
i
c
c
T
T
r
r
u
u
n
n
k
k
Ports using Static Trunk as their trunk method can choose their unique Static GroupID
(also 1~8, 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 trunked 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 about the port aggregation function on the switch, in the
management point of view, the switch supports maximum 8 trunk groups for LACP and
additional 8 trunk groups for Static Trunk. But in the system capability view, only 8 “real
trunked” groups are supported. An LACP trunk group with more than one ready
member-pors is a “real trunked” group. An LACP trunk group with only one or less than
one ready member-port is not a “real trunked” group. Any Static trunk group is a “real
trunked” group.
Per Trunking Group supports a maximum of 12 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:
z
12 ports have already used Static Trunk Group ID 1, the 13th port willing to use the
same Static Trunk Group ID will be automatically set to use the “None” trunking
method and its Group ID will turn to 0. This means the port won’t aggregate with
other ports.
z
14 ports all use LACP Trunk Group ID 1 at most 12 ports can aggregate together and
transit into the ready state.