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New Member

Need help, two stack-3750 clustering and Voice VLAN

hi im cliff, im a newly hired network specialist and this my first experience in a pure IT work.Ive done my CCNA aready last July 10, 2006 but im not yet totally familiar with swith clustering, and voice vlan.

Just need help of the ff:

1.Configure two stack cisco 3750-24s(Core Switch) for clustering and a redundant connection of a couple of cisco 2950s as cluster member.

2.Configure a Voice VLAN.


*Our network has 300+ host 40% voice applications and are 24/7 up. Am i gonna interrupt my network operation with this process of clustering and voice vlan?

*i really need an expert advice about the proper step to this process, with or without interrupting my network?

Attach is my ideal LAN topology for more details.




Re: Need help, two stack-3750 clustering and Voice VLAN

If this is an operational setup, are you sure that there id no connection between the two 3750 switches.

If you want to "stack" the switches, you need to connect stack1 of switch 1 to stack2 of switch 2 and vice versa. This will change the port numbers and they will become like 1/0/1-24 for 1st switch and 2/0/1-24 for second. And yes this may cause a downtime for your network. In order to minimize the downtime, you can prepare configurations in advance

A voice vlan is configured to allow connecting IP phone and PC on the same switchport. Thus the accesslink will carry two VLANs one for data and the other voice vlan. On the access port give command

config-if#switchport voice vlan XXX

Once you configured this VLANs and create DHCP scopes for this your phones will get IP addresses from this new VLAN (assumed you have cisco phones)

Re: Need help, two stack-3750 clustering and Voice VLAN

New Member

Re: Need help, two stack-3750 clustering and Voice VLAN

thank you guys,

also i wanna ask since the 2 3750s stack and other cisco switches are operational, will it really need a downtime for clustering and voice vlan configuration?

Re: Need help, two stack-3750 clustering and Voice VLAN

Once you clustered both the switches, you will lose the configuration on slave. Will need to reconfigure. This will need a downtine, although minimal.

Configuring voice vlans may not require any downtime. Just reset the phone and it will take new ip