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VLAN Setup CISCO SG300 and SIP Gateway

Hopefully someone can shed some light here. I'm quite new to networking and not too sure if I'm doing the right thing here.

We are setting up a new VOIP phone system with SIP gateway for our company. Below is what we have done so far.

Data - VLAN 1 (
Voice - VLAN110 (
SIP gateway -

Router is configured for both VLAN1 and VLAN110. VLAN1 default gateway is and VLAN110 gateway is

PABX is set to VOIP server is set to DHCP server 2 scopes - for data and for voip phones.

I have a cisco SG300-52P switch in layer 3 mode. I have setup both VLANS on the switch. VLAN1 has an interface of and VLAN110 has an interface of PABX is plugged into port 2, port is set to access port untagged VLAN 110. Voip server is plugged into port 3 and port is set to trunk mode. Router is plugged into port 1 and set to trunk.

I can ping PABX ( from Voip server ( Voip phones are booting and getting dhcp scope from dhcp server. PCs are getting correct dhcp scope for data. Everything seems working so far.

However, SIP gateway is plugged into port 4 and port is set to access untagged VLAN110. I can ping from the switch. However I can't ping from either DHCP server or Voip server. I have tried so many things so far and no matter what I do, I'm unable to ping this.

Am I missing any configuration here?

Thank you.

Everyone's tags (1)

Hi @Alchinlong44,I got some

Hi @Alchinlong44,

I got some questions:

  • If you try to ping the SIP Gateway from any host in the VLAN 1, does the ping still fail?
  • Did you check if those hosts have the correct default gateway configured?
  • Why do you have the port to the server as a trunk? Is it necessary to carry more than one VLAN in that port?

Hope to see your answers.


Martin, IT Specialist

Community Member

As Martin saidremove the

As Martin said

remove the trunks from the server port and from the router port

make it plain simple

Voice Devices in Voice Vlan

Data Devices in Data Vlan

and the switch in layer 3 mode will do the routing between them (i never worked with those switches yet ) but the this is working in a classic series Layer 3 switches.


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