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New Member

I have 2 SW with 2 trunk ports / links connecting both together.

Pls. clear my doubts. I have 2 SW with 2 trunk ports / links connecting both together. On each SW ports we have F1/1 & F1/2 connection F1/1 & F1/2 respectively.

On each of those 2 SW are hosts with presumably access link as Fa1/3 each. The question is ?Refer to the exhibit. Which ports could safely be configured with PortFast? (Choose two.) it is the

Trunks links as explain or the access link ?

10 REPLIES
Cisco Employee

Re: I have 2 SW with 2 trunk ports / links connecting both toget

portfast is generally used on ports conneceting the end host stations. However, in the newer IOS for switches, Cisco has launched a new feature to enable the portfast on the trunkports. The command used is " spanning-tree portfast trunk". However as per the exhibit, I would enable the postfast only on port Fas 1/3. So the answer should be Fa 1/3 only.

What are the other options. Is it only the above mentioned options only.

HTH,Please rate if it does.

-amit singh

New Member

Re: I have 2 SW with 2 trunk ports / links connecting both toget

A tricky one here pals. 2 Routers on WAN with are communicating. But a 3rd with LAN subnet address 172.16.1.0/24 is connected on to Router B in the middle between A & C, with subnet address 10.1.1.0/24 & 10.1.2.0/24. However, the Router C LAN subnet address is 192.168.1.0. RtrB and RtrC are configured for RIPv1 and have complete connectivity. RtrA is added to the network. What is the most appropriate RtrA configuration for full connectivity?

Cisco Employee

Re: I have 2 SW with 2 trunk ports / links connecting both toget

A network diagram would help us understanding the question better.Based on the diagram it would be more realistic to put an answer forward.

But there are usaually two things that we can do..

1. comfigure RIPV1 on A

2. Configure a defalt route on A and configure the static routes on router B to reach the subnets on router A. Once this is done you can redistribute the static routes on router B. This way router C will learn the routes to reach the Site A subnet.

-amit singh

New Member

Re: I have 2 SW with 2 trunk ports / links connecting both toget

u can configure portfast only in access link not in trunk.

The switch ports to which u dont want to connect switches(in future) u configure as portfast.simply u can't connect switches to a portfast configured port.

Instead u can have pc's,printers etc..

hope it cleared ur doubt.

New Member

Re: I have 2 SW with 2 trunk ports / links connecting both toget

Thanks guys. I appreciate your instant replies. But, pls. stay around while I pour more of my complications at your help.

Cisco Employee

Re: I have 2 SW with 2 trunk ports / links connecting both toget

sakthi,

Just to update you that you can enable the portfast on the trunk interfaces as well. Have a look at this new feature on Cisco switches.

http://www.cisco.com/univercd/cc/td/doc/product/lan/cat3750/12235se/cr1/cli3.htm#wp1946892

HTH,Please rate if it does.

-amit singh

New Member

Re: I have 2 SW with 2 trunk ports / links connecting both toget

A tricky one here pals. 2 Routers on WAN with are communicating. But a 3rd with LAN subnet address 172.16.1.0/24 is connected on to Router B in the middle between A & C, with subnet address 10.1.1.0/24 & 10.1.2.0/24. However, the Router C LAN subnet address is 192.168.1.0. RtrB and RtrC are configured for RIPv1 and have complete connectivity. RtrA is added to the network. What is the most appropriate RtrA configuration for full connectivity?

Do I need to enable RIP and then add all the subnet address or enable RIP & add just Router A subnet LAN & WAN ? Thanks for your attention

Cisco Employee

Re: I have 2 SW with 2 trunk ports / links connecting both toget

Please see my post above.

Just enable RIP on the router A and include all the subnets that you want to advertise.

-amit singh

New Member

Re: I have 2 SW with 2 trunk ports / links connecting both toget

hmmm i think just enable rip and add rtra's LAN ,WAN classful network..

hop this wud work

New Member

Re: I have 2 SW with 2 trunk ports / links connecting both toget

Actually of the options, the answer I ?d thought wasn?t the answer given and, I ? ve my doubts about that. The answer said that, just enable RIP and add the subnet 10.0.0.0 and 172.16.0.0. But, the 192.168.1.0 wasn?t added in the option. Whereas my chosen option would have added all the newt.

I don?t know if this is having to do with the recent IOS too ?

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