H3C Technologies H3C SecPath F1000-E - Manual (Page 211)

18
Item Description
Mode
STP can operate in STP mode, RSTP mode, or MSTP mode.
• STP mode: All ports of the device send out STP BPDUs.
• RSTP mode: All ports of the device send out RSTP BPDUs. If the device
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 device send out MSTP BPDUs. If the device
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
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.
z The network diameter applies to only the CIST, and not to MSTIs.
It takes effect only after you configure it on the root bridge. Each
MST region is regarded as a device.
z After you set the network diameter, you cannot set the timers.
Instead, the device calculates the forward delay, hello time, and
max age automatically.
Timer Forward Delay
Set the delay for the root and
designated ports to transit to the
forwarding state.
The length of the forward delay time is
related to the network diameter of the
switched network. Typically, the larger
the network diameter is, the longer the
forward delay time should be. Note
that if the forward delay setting is too
small, temporary redundant paths may
be introduced; if the forward delay
setting is too big, it may take a long
time for the network to converge. H3C
recommends that you use the default
setting.
z The settings of hello
time, forward delay and
max age must meet a
certain formula.
Otherwise, the network
topology will not be
stable. H3C
recommends that you set
the network diameter and
then have the device
calculate the forward
delay, hello time, and
max age automatically.
z You cannot configure
both the network