Brocade Network OS Administrator’s Guide v4.1.1 - Manual (Page 421)

3. Specify the bridge priority. The range is 0 through 61440 and the priority values can be set only in
increments of 4096. The default priority is 32678.
switch(conf-stp)# bridge-priority 20480
4. Specify the bridge priority for a specific VLAN.
switch(conf-stp)# bridge-priority 20480 vlan 10
Specifying the bridge forward delay
In STP, RSTP, MSTP, PVST+, or R-PVST+ mode, use the forward-delay command to specify how
long an interface remains in the listening and learning states before the interface begins forwarding all
spanning tree instances. The valid range is from 4 through 30 seconds. The default is 15 seconds. The
following relationship should be kept:
2*(forward_delay - 1)≥ max_age ≥ 2*(hello_time + 1)
Additionally, you may specify the forward delay for a specific VLAN. If the VLAN parameter is not
provided, the priority value is applied globally for all per-VLAN instances. However, for the VLANs that
have been configured explicitly, the per-VLAN configuration takes precedence over the global
configuration.
NOTE
On the Brocade VDX 8770, the VLAN value can be 1 through 4086. VLAN IDs 4087 through 4094 are
internally-reserved VLAN IDs. On all other Brocade VDX switches, the VLAN value can be 1
through 3962, as 3963 through 4094 are reserved.
To specify the bridge forward delay, perform the following steps from privileged EXEC mode.
1. Enter the configure terminal command to change to global configuration mode.
switch# configure terminal
2. Enter the protocol command to enable STP, RSTP, MSTP, PVST+, or R-PVST+.
switch(config)# protocol spanning-tree stp
3. Specify the bridge forward delay.
switch(conf-stp)# forward-delay 20
4. Specify the bridge forward delay for a specific VLAN.
switch(conf-stp)# forward-delay 20 vlan 10
Specifying the bridge maximum aging time
In STP, RSTP, MSTP, PVST+, or R-PVST+ mode, use the max-age command to control the maximum
length of time that passes before an interface saves its BPDU configuration information.
When configuring the maximum aging time, you must set the max-age to be greater than the hello time.
The range is 6 through 40 seconds. The default is 20 seconds. The following relationship should be
kept:
2*(forward_delay - 1) ≥ max_age ≥ 2*(hello_time + 1)
Additionally, you may specify the maximum aging for a specific VLAN. If the VLAN parameter is not
provided, the priority value is applied globally for all per-VLAN instances. However, for the VLANs that
have been configured explicitly, the per-VLAN configuration takes precedence over the global
configuration.
NOTE
On the Brocade VDX 8770, the VLAN value can be 1 through 4086. VLAN IDs 4087 through 4094 are
internally reserved VLAN IDs. On all other Brocade VDX switches, the VLAN value can be 1
through 3962, as 3963 through 4094 are reserved.
To specify the bridge maximum aging time, perform the following steps from privileged EXEC mode.
Specifying the bridge forward delay
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