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262
C
HAPTER
9: B
RIDGE
-
WIDE
P
ARAMETERS
bridge spanningTree
✓
3500
✓
9000
✓
9400
✓
3900
✓
9300
stpMaxAge
Determines when the stored CPDU configuration message is discarded
from the bridge’s memory if the bridge is the root bridge. The current
value is shown in the bridgeMaxAge field of the
bridge display
.
Valid Minimum Abbreviation
b sp stpm
Important Considerations
■
If the value is too small, the STP may reconfigure the topology too
often, causing temporary loss of connectivity in the network.
■
If the value is too large, the network may take longer than necessary
to adjust to a new STP configuration after a topology change such as
the restarting of a bridge.
■
A conservative value assumes a delay variance of
2
seconds per hop.
The recommended and default value is
20
seconds.
■
Although the possible range for stpMaxAge is 6 – 40, the available
range is constrained by the following inequalities:
■
2 x (stpForwardDelay - 1 second) >= stpMaxAge
■
stpMaxAge >= 2 x (stpHelloTime + 1 second)
Options
Prompt Description Possible Values [Default]
STP max age Value (in seconds) when the
stored configuration message
information is deemed too old
and is discarded
6 – 40 seconds 20 (factory
default), or
current value