Brocade FastIron Ethernet Switch Platform and Layer 2 Switching Configuration Guide User Manual
Page 253
Default STP states (Continued)
TABLE 43
Device type
Default STP type
Default STP state
Default STP state of new VLANs
1
Base L3 image default
No span
Disabled
Disabled
ICX 6650
Layer 2 switch
MSTP
2
Enabled
Enabled
Layer 3 switch
MSTP
Disabled
Disabled
1. When you create a port-based VLAN, the new VLAN STP state is the same as the default STP state on the device. The new VLAN
does not inherit the STP state of the default VLAN. The Single Spanning Tree Protocol (SSTP) is another type of STP. SSTP includes all
VLANs on which STP is enabled in a single spanning tree. Refer to
on page 311.
2. MSTP stands for “Multiple Spanning Tree Protocol”. In this type of STP, each port-based VLAN, including the default VLAN, has its own
spanning tree. References in this documentation to “STP” apply to MSTP.
The following table lists the default STP bridge parameters. The bridge parameters affect the entire
spanning tree. If you are using MSTP, the parameters affect the VLAN. If you are using SSTP, the
parameters affect all VLANs that are members of the single spanning tree.
Default STP bridge parameters
TABLE 44
Parameter
Description
Default and valid values
Forward Delay The period of time spent by a port in the listening and learning state
before moving on to the learning or forwarding state, respectively.
The forward delay value is also used for the age time of dynamic
entries in the filtering database, when a topology change occurs.
15 seconds
Possible values: 4 - 30
seconds
Maximum Age The interval a bridge will wait for a configuration BPDU from the root
bridge before initiating a topology change.
20 seconds
Possible values: 6 - 40
seconds
Hello Time
The interval of time between each configuration BPDU sent by the
root bridge.
2 seconds
Possible values: 1 - 10
seconds
Priority
A parameter used to identify the root bridge in a spanning tree
(instance of STP). The bridge with the lowest value has the highest
priority and is the root.
A higher numerical value means a lower priority; thus, the highest
priority is 0.
32768
Possible values: 0 - 65535
NOTE
If you plan to change STP bridge timers, Brocade recommends that you stay within the following
ranges, from section 8.10.2 of the IEEE STP specification. 2 * (forward_delay -1) >= max_agemax_age
>= 2 * (hello_time +1)
The following table lists the default STP port parameters. The port parameters affect individual ports
and are separately configurable on each port.
Spanning Tree Protocol
FastIron Ethernet Switch Platform and Layer 2 Switching Configuration Guide
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