239
Switch(Config-Ethernet1/2)#no spanning-tree
8.3.7 spanning-tree format
Command:spanning-tree format standard | privacy | auto
no spanning-tree format
Function:
Configure the format of the port packet so to be interactive with products of
other companies.
Parameter
：
standard
：
The packet format provided by IEEE
privacy
：
Privacy packet format, which is compatible with CISCOequipments.
auto
：
Auto identified packet format, which is determined by checking the
format of the received packets.
Default
：
Privacy Packet Format
Command Mode
：
Port Mode
Usage Guide:
As the CISCO has adopted the packet format different with the one provided by
IEEE, while many companies also adopted the CISCO format to be CISCO compatible,
we have to provide support to both formats. The standard format is originally the one
provided by IEEE, and the privacy packet format is CISCO compatible. In case we are
not sure about which the packet format is on partner, the AUTO configuration will be
preferred so to identify the format by the packets they sent. The privacy packet format is
set by default in the concern of better compatibility with previous products and the
leading companies. Also the packet format will be privacy format before receiving the
partner packet when configured to AUTO.
When the format is not AUTO and the received packet format from the partner does
not match the configured format, we set the state of the port which receives the
unmatched packet to DISCARDING to prevent both sides consider themselves the root
which leads to circuits.
When the AUTO format is set, and over one equipment which is not compatible with
each other are connected on the port (e.g. a equipment running through a HUB or
Transparent Transmission BPDU is connected with several equipments running MSTP),
the format alter counts will be recorded and the port will be disabled at certain count
threshold. The port can only be re-enabled by the administrator.
Example:
Switch(Config)#interface ethernet 0/0/2
Switch(Config-Ethernet-0/0/2)#spanning-tree format standard
8.3.8 spanning-tree forward-time
