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6509 MSFC2 network design question


I will be migrating a 6509 Sup1a flat campus network to 6509 Sup2 MSFC2.

I am interested in recommendations for the design.


6+ closets each with up to 5 3550 and 3548 switches using gigastack.

2 gig fibers back to 1 central 6509 from each closet. There is one 6509. This will have 2 sup2a MSFC2.

Users DHCP'd.

Network equipment has in it's own class C.

This is all on VLAN 1 at the moment, I want to separate out a management VLAN for the network equipment and user VLANs.

What would you recommend to run in this collapsed core scenario ?

I would like to load balance on the fibers and also provide redundancy to the closets.




Re: 6509 MSFC2 network design question


you have mentioned that you have 6509-sup1 & 6509-sup2 with MSFC2,

since you say that you wanted to segment the network & hav a network redundant, u need to have layer 3 on both the 6509's(bcoz ur core will 6509)currently u have mentioned only 6509-sup2 has MSFC2.

HSRP needs to be implemented for network redundant between to 6509's(only if both has got layer 3)

regd. fiber connectivity, what you can do is, can implement ether channeling(combing max of 4 ports in to 1 logically port)

dhcp can be implemented on either 3550 or 3548 siwtch bcoz if you network is running HSRP then implementing DHCP on the core switches is not recommended.

hope this helps.

rate this post if cleared.


Re: 6509 MSFC2 network design question

I would make a subnet for each closet and etherchannel each connection seeing that you have 2 fibers to the closet . If I understand correctly you have a separate subnet for net management which in case I would create a combined trunk /etherchannel to each closet . You can either run your setup as client/server or you can run transparent mode for the trunks. The etherchannel will provide your redundancy for the links. Not knowing your current address scheme you would have to figure that out . If everything is in 1 big subnet I would break it down into smaller pieces and assign a piece to each closet . This will involve readdressing and changing default gateways ,masks etc........... Breaking up your 1 big broadcast domain should help in your response times and loads...

New Member

Re: 6509 MSFC2 network design question

Hi Glen, interesting, I didn't think of etherchannel.

So I would bond the 2 gig fibers to each closet, using eitherchannel.

1. Create 2 vlans for each closet,

1 vlan for management of switches. /25

1 vlan for client user PC's./24

2. Create SVI for each vlan with a route on the 6509.

3. Add DHCP helper addresses for each closet.

Does that sound about right ?


Re: 6509 MSFC2 network design question

Exactly what I was thinking ....