Table of Contents
Advertisement
Question
Is
the
device
running
MSTP, STP, or RSTP, and
working
with
a
Cisco
PVST+ device?
Do the topologies of MSTIs
meet the design?
Are
there
as
few
overlapping
paths
possible among MSTIs?
Does a TC attack exist to
cause frequent STP status
changes on any ports?
VRRP
Is the handshake interval
correctly set?
Are
the
handshake
intervals of the two ends
the same?
Command or method
display stp
display
current-configuration
interface
as
display stp tc
display stp history
display vrrp
13
Result
Remarks
tree feature on the ports.
□OK
As a best practice to avoid
interoperability issues, set
□Not OK
up a Layer 3 connection to
□Not related
the Cisco device.
If the topologies deviate
from the design, reassign
ports to VLANs and revise
the VLAN and instance
□OK
mappings.
□Not OK
For optimal load balancing,
plan
□Not related
VLAN-to-instance
mappings
overlapping paths among
different MSTIs.
Examine
items in the command
output for TC attacks:
•
Incoming
outgoing
BPDU statistics.
•
Historical
calculation
information.
There is a risk of TC attack
if
frequent
changes occur on a stable
network.
Make
□OK
configured
settings:
□Not OK
•
Configure
□Not related
connected to end-user
devices as edge ports,
and
guard.
disable the spanning
tree feature on the
ports.
•
Disable the spanning
tree feature on ports
connected to devices
that do not support
spanning
protocols.
•
Do
TC-BPDU guard.
Change
interval to 3 seconds if the
□OK
number of VRRP groups is
smaller than 5.
□Not OK
If five or more VRRP
□Not related
groups exist, assign three
or five VRRP groups to one
group, and configure the
VLANs
and
to
minimize
the
following
and
TC/TCN
port
role
STP
status
sure
you
have
the
following
ports
enable
BPDU
Alternatively,
tree
not
disable
the
handshake
Advertisement
Table of Contents
Troubleshooting
