Stp Max-Hops - H3C s3600 series Command Manual

View
Ethernet port view
Parameters
None
Description
Use the stp loop-protection command to enable the loop guard function on the current port.
Use the undo stp loop-protection command to restore the loop guard function to the default state on
the current port.
By default, the loop guard function is disabled.
A switch maintains the states of the root port and other blocked ports by receiving and processing
BPDUs from the upstream switch. These BPDUs may get lost because of network congestion or
unidirectional link failures. If a switch does not receive BPDUs from the upstream switch for a certain
period, the switch selects a new root port; the original root port becomes a designated port; and the
blocked ports turn to the forwarding state. This may cause loops in the network.
The loop guard function suppresses loops. With this function enabled, if link congestions or
unidirectional link failures happen, a root port becomes a designated port, and the port turns to the
discarding state. The blocked port also becomes the designated port and the port turns to the
discarding state, that is, the port does not forward packets and thereby loops can be prevented.
Examples
# Enable the loop guard function on Ethernet 1/0/1.
<Sysname> system-view
System View: return to User View with Ctrl+Z.
[Sysname] interface Ethernet 1/0/1
[Sysname-Ethernet1/0/1] stp loop-protection

stp max-hops

Syntax
stp max-hops hops
undo stp max-hops
View
System view
Parameters
hops: Maximum hop count to be set. This argument ranges from 1 to 40.
Description
Use the stp max-hops command to set the maximum hop count for the MST region the current switch
belongs to.
Use the undo stp max-hops command to restore the maximum hop count to the default.
By default, the maximum hop count of an MST region is 20.
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