STP BPDU GUARD

• If BPDU received from end host, immediately shut down the port
• Instead of blocking BPDU(as in BPDU filter)  make the port into error disable state(traffic blocked).
• After port going into error disable state, port can up
• if error disable recovery timer expires
• or, manually shutdown the port then bringsup.
•  It is the more secured implementation of filtering STP.
• Also config with PortFast on global mode
• interface level will over ride global config
• to check error disable recover timer enable or not use show cmd
• show errdisable recvoery
• Enable error disable recovery timer
• errdisable recovery interval 30 on global mode (some times not enabled, verify by above cmd, then use below cmd)
• errdisable recovery cause bpdugaurd because there are so many causes the port goto errdisable state
• spanning-tree portfast bpdugaurd default
• spanning-tree bpdugaurd default