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VLAN question


I will setup the call center in China, Attached the design. L3 routing is enbaled to all switches. I have some question about the design:

1. the spanning tree should be enabled. is the trunk between "switch C" and "switch D" disabled automatically for normal operation?

2. what problem will happen if the trunk between "switch A" and "switch B" is broken?

3. Can I force some Vlan traffic going to the trunk between "switch A" and "switch C" (e.g. Pc traffic); some Vlan traffic going to the trunk between "switch B" and "switch D" (e.g. voice traffic). if so, what is the sample config of four switches?

4. If I enable the "item 3" and the trunk between "switch A" and "switch C" is broken, can the traffic go to the trunk between "switch B" and "switch D"?


New Member

Re: VLAN question

Hi anita,

After viewing your Network Diagram and it shows that

* Switch A is the Source for all PC vlan's

* Switch B is the Source for all Voice vlan's.

Since you are setting up a Network for a call centre it requires high availability, For that you need redundancy in your Network Design.

Can you clarify me on the following , so that i can help you outin this.

1. What series of switch you are having for access and core, since your design shows 2tier model , so it has only CORE and ACCESS.

2. Whether your Data and Voice network needs to be isolated

3. Do u have extra ports in access and core for redundancy.

The following suggestions can i give based on the Diagram provided by you...

1. Create Both voice and PC vlans in both core switch.

2. Each access switch ( Independent of PC access or IP Phone access switch ) must have connectivity to core switch.

3. Running HSRP between core switches for each VLAN's.

4. Running Etherchannel between your core switches

Feel Free to contact...

New Member

Re: VLAN question

1. Distribute is CAT 37xx, core CAT 4503. I haven't show the "access switch"

2. yes. if possible

3. for access layer, there is no redundancy. for distribute / core layer, it has redundancy

regarding your suggestion

1. yes

2. access switch will connect to distribute layer

3. yes

4. not understand "etherchannel", what is it? is it fiber?


New Member

Re: VLAN question


the access switch is 3com switch


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