Chapter 14 Switch Configuration
NetAtlas Workgroup User’s Guide
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14.4 Link Aggregation
Link aggregation (trunking) is the grouping of physical ports into one logical higher-capacity
link. You may want to trunk ports if for example, it is cheaper to use multiple lower-speed
links than to under-utilize a high-speed, but more costly, single-port link.
However, the more ports you aggregate then the fewer available ports you have. A link
aggregation group is one logical link containing multiple ports.
The first port must be physically connected when forming a trunk group.
Hello Time This is the maximum time (in seconds) a device can wait without receiving a BPDU
before attempting to reconfigure. All device ports (except for designated ports) should
receive BPDUs at regular intervals. Any port that ages out STP information (provided
in the last BPDU) becomes the designated port for the attached LAN. If it is a root
port, a new root port is selected from among the device ports attached to the network.
The allowed range is 6 to 40 seconds (20 is the default).
Max Age This is the time interval in seconds between BPDU (Bridge Protocol Data Units)
configuration message generations (by all devices in RSTP or the root device in STP).
The allowed range is 1 to 10 seconds (2 is the default).
Forwarding
Delay
This is the maximum time (in seconds) a device will wait before changing states. This
delay is required because every device must receive information about topology
changes before it starts to forward frames. In addition, each port needs time to listen
for conflicting information that would make it return to a blocking state; otherwise,
temporary data loops might result. The allowed range is 4 to 30 seconds (15 is the
default).
Rapid Spanning Tree Protocol
Active Select this option to enable STP.
Bridge Priority Priority is used in determining the root device, root port and designated port. The
device with the highest priority (lowest numeric value) becomes the RSTP root device.
If all devices have the same priority, the device with the lowest MAC address will then
become the root device. The allowed range is 0 to 65535 (32768 is the default).
The lower the numeric value you assign, the higher the priority for this bridge.
Priority determines the root bridge, which in turn determines Hello Time, Max Age
and Forward Delay.
Max Age This is the maximum time (in seconds) a device can wait without receiving a BPDU
before attempting to reconfigure. All device ports (except for designated ports) should
receive BPDUs at regular intervals. Any port that ages out STP information (provided
in the last BPDU) becomes the designated port for the attached LAN. If it is a root
port, a new root port is selected from among the device ports attached to the network.
The allowed range is 6 to 40 seconds (20 is the default).
Hello Time This is the time interval in seconds between BPDU (Bridge Protocol Data Units)
configuration message generations (by all devices in RSTP or the root device in STP).
The allowed range is 1 to 10 seconds (2 is the default).
Forwarding
Delay
This is the maximum time (in seconds) a device will wait before changing states. This
delay is required because every device must receive information about topology
changes before it starts to forward frames. In addition, each port needs time to listen
for conflicting information that would make it return to a blocking state; otherwise,
temporary data loops might result. The allowed range is 4 to 30 seconds (15 is the
default).
Apply Click Apply to save your changes back to the switch.
Table 66 Switch Configuration: Multiple STP Conf. (continued)
LABEL DESCRIPTION
