Allied Telesis AT-S63 - Manual (Page 571)

AT-S63 Management Software Command Line User’s Guide
Section V: Spanning Tree Protocols 571
portpriority Specifies the port’s priority. This parameter is used as a
tie breaker when two or more ports are determined to
have equal costs to the root bridge. The range is 0 to
240 in increments of 16. There are sixteen increments,
as shown in Table 24 on page 571. You specify the
increment of the desired value. The default is 128,
which is increment 8.
stpid Specifies the ID number of an MSTI in which the VLAN
of a port is a member. This parameter is used with the
INTPORTCOST and PORTPRIORITY parameters to
assign different path costs and priority values to
untagged and tagged ports whose VLANs belong to
more than one MSTI. You can specify more than one
MSTI at a time (e.g., 4,6,11). If the VLANs of a port
belong to just one MSTI, you can omit this parameter.
Description
This command sets a port’s MSTP settings. The command is illustrated in
two syntaxes to represent the two groups of MSTI port parameters. The
first group is referred to as generic parameters. They are set just once on
a port, regardless of the number of MSTIs where a port is a member.
These parameters are the external path cost and edge port and point-to-
point port designations.
The second group can be applied independently on a port on a per-MSTI
basis. There are two parameters in this group — internal path cost and
priority. A port whose VLANs are members of different MSTIs can have
different settings in each MSTI. The MSTI is identified with the STPID
parameter. You can omit the STPID parameter if a port is a member of one
or more VLANs that all belong to the same MSTI, or if you want to assign
the port the same path cost or priority value in all of its MSTI assignments.
Table 24. Port Priority Value Increments
Increment Port Priority Increment Port Priority
0 0 8 128
1 16 9 144
2 32 10 160
3 48 11 176
4 64 12 192
5 80 13 208
6 96 14 224
7 112 15 240