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When used in an MSTP network, if root guard blocks a boundary port in the CIST, the port is also blocked
in all other MST instances.
Enabling Portfast BPDU guard and loop guard at the same time on a port results in a port that remains
in a blocking state and prevents traffic from flowing through it. For example, when Portfast BPDU guard
and loop guard are both configured:
● If a BPDU is received from a remote device, BPDU guard places the port in an err-disabled blocking
state and no traffic is forwarded on the port.
● If no BPDU is received from a remote device, loop guard places the port in a loop-inconsistent
blocking state and no traffic is forwarded on the port.
tc-flush-standard
Enable the MAC address flushing after receiving every topology change notification.
Syntax
tc-flush-standard
To disable, use the no tc-flush-standard command.
Defaults Disabled.
Command Modes CONFIGURATION
Supported Modes Full–Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
8.3.16.1 Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
By default, the sytem implements an optimized flush mechanism for MSTP. This mechanism helps in
flushing the MAC addresses only when necessary (and less often) allowing for faster convergence during
topology changes. However, if a standards-based flush mechanism is needed, this knob command can be
turned on to enable flushing MAC addresses after receiving every topology change notification.
786 Multiple Spanning Tree Protocol (MSTP)