Golgappa.net | Golgappa.org | BagIndia.net | BodyIndia.Com | CabIndia.net | CarsBikes.net | CarsBikes.org | CashIndia.net | ConsumerIndia.net | CookingIndia.net | DataIndia.net | DealIndia.net | EmailIndia.net | FirstTablet.com | FirstTourist.com | ForsaleIndia.net | IndiaBody.Com | IndiaCab.net | IndiaCash.net | IndiaModel.net | KidForum.net | OfficeIndia.net | PaysIndia.com | RestaurantIndia.net | RestaurantsIndia.net | SaleForum.net | SellForum.net | SoldIndia.com | StarIndia.net | TomatoCab.com | TomatoCabs.com | TownIndia.com
Interested to Buy Any Domain ? << Click Here >> for more details...


Hi Guys..

I hv a confusion in my mind. Plz help me to clear my concept.

How a port respond when a PortFast port receives any BPDU.
Please make sure that BPDU Guard, ROOT Guard are not
considered in this scenario. Just a spanning tree without
any enhancement.

Will the port goes through STP port state??? As we knw that
PortFast bypass the Listening & Learning State? How it will
respond when a BPDU (Inferior or Superior) is received on
that Port.

Thanks in advance. Waiting for Replay.

Answers were Sorted based on User's Feedback



Hi Guys.. I hv a confusion in my mind. Plz help me to clear my concept. How a port respond whe..

Answer / jitu

Yes, this really is the case. However, I do think there is
some confusion as to what happens to a Portfast enabled port
when it receives a BPDU. Upon receipt of a BPDU on a
Portfast enabled port, the port will immediately loose its
PortFast feature. This does not mean that the port will
show Portfast disabled in the "show spanning-tree summary"
output. Rather it means it will act as a normal STP port
and transistion through the STP states and will eventually
end up in either a blocking state or a forwarding state.



If the BPDUs that were arriving on the port were
"non-superior" BPDUs, the port would transistion to the
blocking state. Once these BPDUs stop the port would
recover and again participate in Portfast.



If the BPDUs that were arriving on the port were "superior"
BPDUs (means a lower bridge priority), then the port would
transistion to the forwarding state. This can cause a
permanent STP recalculation throughout your switch network.



Enabling BPDU Guard in addition to Portfast will prevent
bridging loops and/or topology changes from happening,
because upon receipt of BPDUs (superior or not), the BPDU
Guard feature immediately err-disables the port and must
manually be reenabled.

Right Mr... sahin ( hehhehe)

Is This Answer Correct ?    1 Yes 0 No

Hi Guys.. I hv a confusion in my mind. Plz help me to clear my concept. How a port respond whe..

Answer / parshant jaswal

HI SHAHIN
1. WHEN YOU ARE ENABLING SPANNING TREE PORTFAST ON ANY
INTERFACE THAT MEAN YOU ARE KILL SPANNING TREE ON THE PORT.
PORT NEVER TAKE PARTICIPATES ON THE ELACTION OF ROOT BRIDGE.
2. AND PORTFAST FEATURE BYPASS THE LISTENING, LEARNING
AND MAX AGE
3. YOU CAN ENABLE BPDU GUARD FEATURE ON ALL NON-TRUNKING
FOR TO PROTECT YOUR TOPOLOGY TO RECEIVING ANY BPDU
4. ROOT GUARD FEATURE ENABLE ONLY BETWEEN ROOT AND NON
ROOT BRIDGE SWITCH AND NEVER USE IT BETWEEN PRIMARY AND
SECONDRY ROOT BRIDGE.

Is This Answer Correct ?    1 Yes 0 No

Post New Answer

More CCNA Interview Questions

Name the vtp modes?

0 Answers  


What is the regional telco office called, where the customers local loop terminates? A.) Demarc B.) DTE C.) DCE D.) CO E.) CPE

1 Answers  


Identify 3 characteristics of a MAC address? A.) Burned into the NIC B.) 48 bits long C.) Length is 32 bits D.) Used to identify a host device E.) Contains a network portion and a host portion

2 Answers  


Differnce between the communication and transmission?

0 Answers  


What are the netbios and netbeui?

0 Answers  


hi friends i am jitendera kumar sinha.i have a question in mind that what is the diffrence between router and l3 switch i serched on google and found that switch L3 is best in lan and router are best in wan and switch are more faster then router.beside that any short of technical diffrence if you body know then plz plz and plz reply. my 2nd question is that why we canot replace router with L3 switches (donot tell that it is costly then router).i want any technical cause. this is 1 am hope in noon when ever i logg again i will find the answer posted by you. thanks onse again plz pzl make reply thanks jitendera kumar sinha jitenerasinha.it@gmail.com

5 Answers  


Can you explain tunneling?

0 Answers   CCIE,


Identify the command that will display the RIP routes entering and leaving the router? A.) Router(config)# debug ip rip B.) Route# debug ip rip C.) Router>debug ip rip D.) Router# debug rip routes

1 Answers  


Identify the type of hardware required to connect a Token ring network to an Ethernet network? A.) Repeater B.) TR-Enet C.) Router D.) Token Ring to Ethernet translation hub

1 Answers  


Which of the following is an example of the Session Layer? A.) TCP B.) SQL C.) IP D.) X-Windows E.) Token Ring F.) LLC

2 Answers  


Repeaters work at which layer of the OSI model? A.) Network B.) Session C.) Transport D.) Physical

4 Answers  


What is the default LMI type? A.) Cisco B.) ANSI C.) IETF D.) Q933a

2 Answers  


Categories