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SG300-52 and Auto Voice VLAN

I have an SG300-52 in the field and the site recently picked up some VOIP phones. I currently have the following

Existing VLAN2 = Data network

Created VLAN3 = Voice network

Under voice VLAN properties I set the Voice VLAN ID=3 and enabled Auto Voice VLAN.

Trunked all ports, setting VLAN2 (data) as untagged and VLAN3 (voice) as Tagged

When the site plugs a phone into the switch, it correctly joins VLAN3 and obtains an IP address, but the data VLAN suddenly changes to VLAN1, even though I have VLAN1 marked as forbidden on all ports.

I'm at a loss as to why this is happening. Any suggestions?


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SG300-52 and Auto Voice VLAN

Wrong forum, post in "small business switches". You can move your posting using the Actions panel on the right.

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SG300-52 and Auto Voice VLAN

I believe I figured out why this one happened. The macro setting for smartports had the default vlan still set to 1, so I guess when the the phone+computer was detected the port was reconfigured to put data on VLAN1.

Per a suggestion in another post, I turned smartports off and suddenly lost access to the management VLAN (VLAN4) on the switch. Nothing on that VLAN is responding, however the devices on the data and voice VLAN are still communicating. The link between the router and switch for the management VLAN is a trunk port setup with tagging.



SG300-52 and Auto Voice VLAN

Hi Denny, you're correct the voice macro needs to be modified to reflect vlan 2 for data. Also, don't manually configure any ports that you connect a phone to, otherwise it conflicts with the software.

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-Tom Please mark answered for helpful posts
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Re: SG300-52 and Auto Voice VLAN

Hi Tom,

Thank you for the reply.

I finally got it all figured out. The Smartports are working as expected. What wasn't expected was the end user hooking the stuff up. Once someone more knowledgable got there and plugged stuff in correctly, it all worked.

Thank you,


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