How to separate data between different Trunks?

Posted on 2009-04-30
Last Modified: 2012-05-06
Hello all! I'll get straight to the problem. I have two new Cisco Catalyst 2960G switches I'm setting up. I have two trunk links between them with spanning tree enabled and need to configure them so that only VOIP traffic goes through one trunk link, and all other data goes over the other trunk link. I was going to use VLANS, but there are many switches within the company and they're all running off of VLAN 1. I need to leave the VOIP traffic on VLAN 1. As far as I can tell, you can not disable VLAN 1 traffic from either of the trunking ports. I don't have the time to go into each switch and change the VLAN configurations, except on these two new ones. Is there another way, or maybe a configuration I'm not aware of?
Question by:sfjcpu
    LVL 32

    Accepted Solution


    I understand you still want to use VLAN1 however, there are known security expolits concerning VLAN1 and Security Best Practices recommend never using VLAN1.

    However, you can remove vlan1 from the trunk via the following;

    switchport trunk allowed-vlans 2,3,4,5,6,7,8 ...   (1 is not include so it will not trunk it, must be done on both sides)

    Likewise you seperate which vlans are on which trunks by using the same methodology

    harbor235 ;}


    Author Closing Comment

    Worked perfectly! Only thing, it didn't like the dash inbetween allowed and vlans, removed that and it accepted the command. Thanks!

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