R3166-R3206-HP High-End Firewalls Network Management Configuration Guide-6PW101

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Item Descri
p
tion
BPDU Guard
Whether to enable BPDU guard globally:
• Enable—Globally enable BPDU guard.
• Disable—Globally disable BPDU guard.
BPDU guard can protect the firewall from malicious BPDU attacks, thus making
the network topology stable.
Mode
STP can operate in the following mode:
• STP—All ports of the firewall send out STP BPDUs.
• RSTP—All ports of the firewall send out RSTP BPDUs. If the firewall detects that
it is connected with a legacy STP device, the port connecting with the legacy
STP device will automatically migrate to STP-compatible mode.
• MSTP—All ports of the firewall send out MSTP BPDUs. If the firewall detects
that it is connected with a legacy STP device, the port connecting with the
legacy STP device will automatically migrate to STP-compatible mode.
Max Hops
Set the maximum number of hops in an MST region to restrict the region size.
The setting can take effect only when it is configured on the regional root bridge.
Path Cost Standard
Specify the standard for path cost calculation. It can be Legacy, IEEE
802.1D-1998, or IEEE 802.1T.
Bridge Diameter (also
called network diameter,
which cannot be
configured together with
the timers)
Any two stations in a switched network are interconnected through a specific
path composed of a series of devices. The bridge diameter (or the network
diameter) is the number of devices on the path composed of the most devices.
After you set the network diameter, you cannot set the timers. Instead, the firewall
calculates the forward delay, hello time, and max age automatically.
The configured network diameter is effective for CIST only, and not for MSTIs.
Timers (The network
diameter and the timers
cannot be configured at
the same time)
• Forward Delay
Set the delay for the root and designated ports to transit to the forwarding state.
• Hello Time
Hello time is the interval at which the firewall sends hello packets to the
neighboring devices to ensure that the paths are fault-free.
• Max Age
Max age determines how long a configuration BPDU can be held by the firewall.
IMPORTANT:
The settings of hello time, forward delay and max age must meet a certain formula.
Otherwise, the network topology will not be stable. HP recommends you to set the
network diameter and then have the firewall calculate the forward delay, hello time,
and max age automatically.