Configure a Cisco SG300 for Auto Voice VLAN Setup

The Cisco SG300 range is a entry business grade switch. Depending on where you sit on the fence of Old School IT OG or not will dictate if you like the Web GUI it comes with. Personally, I prefer the CLI presented in CATOS (Showing my age now) and IOS Switches.

While the SG300 series of switch has a CLI the syntax is somewhat different for from its IOS counterparts so In a way you are kind of obligated to use the Wb GUI

I recently faced an issue where I had to introduce several SG300’s to an already existing Cisco Network. This network had multiple VLANS and the major caveat was VoIP Phones which the customer wanted to be auto placed into the Voice VLAN Automatically

the purpose of this Lesson is to describe how to Configure a Cisco SG300 Switch with Multiple VLANS and configure it in a manner so it will auto configure ports for a Voice VLAN when you connect a IP bassed telephone




Assign VLANS to Ports

Now that we have the VLANS created we can start to assigning our ports. Points to note here

– Do not really need to worry about Excluding any of the VLANS unless we specifically want to deny access to a particular network
– Our Trunk Port needs to be Tagged in Every VLAN so this scenario 201,(Management) 204 (Corporate) 205 (Telephone)


Vlan 1


we are not going to do much with this, its the default VLAN


Ports 25, 26 we are going to Leave the configuration for VLAN 1 so we can connect to the Switch

VLAN 201 Management



Notice we have port 27 Untagged in this VLAN – The reason for this is that we need a port up in this VLAN before we can specify the Management VLAN which will before when we configure the device with its management IPV4 details


VLAN 204 – Corporate


every port that we want our Corporate Network we want to have untagged (Ignore Ge21) in this example


VLAN 205 – Voice


For our Voice VLAN we want to Tag all ports we intend to use on our telephone network. In this example VLAN 205


Auto Voice Vlan Configuration


The SG300 switch has the ability to auto detect when a phone is plugged into it and can then begin to auto tag that port with your Voice VLAN frame (205) – this is done by reffering to a MAC address table and looking up MAC address’s that belong to vendor phones as per below this is available in the telephone OU section of the configuration

Here we can add vendor MAC address’s if required


If we want the auto voice configuration to work then what we need to do is tell the switch what our Voice VALN is – this can be done in the Auto voice VLAN Properties. here we have told the switch

– Voice VLAN is 205
-We want Auto Voice VLAN enabled

Configuring the Management IP of the device


We want to configure the management interface with the IP address Schema -Asper below



The important thing to remember here is as follows


– Configure the IP Address, SM and Default Gateway First
– Save the config and then configure the Management VLAN 201 after
– Before we can selevt this from the drop down we need to ensure that we have a port (Gi27) that is untagged in this VLAN as per the above

Configuring your Trunk Ports


our trunk Port For our Corprate network we want to have ‘Untagged’
However we ant to ‘TAG’ Our Voice VLAN


Configure Uplink of Cisco Switch


The trunk Port and the encapsulation needs to be specified as follows in the command line

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.