GC728XP Cannot Get DHCP or VLANs to Work

Question

Hi all,&nbsp;I have two of these GC728XP switches (Firmware 1.0.5.35) that were just being used as basic switches for VOIP phones without any configuration!&nbsp;My setup is Comcast Xfinity modem then IP out on 10.0.0.1 to Netgear GC728XP switch on port g24. I set the switch to Static IP 10.0.0.2 with Default Gateway 10.0.0.1. I can plug a laptop into any port, and get a DHCP 10.0.0.x address and out to the web.&nbsp;I needed to add a VLAN manually (without Insight) for a PC and a VOIP phone which I did following the user manual.&nbsp;VLAN: I have ports g13 &amp; g14 set as VLAN106 (for room 106) with g13 &amp; g14 removed from VLAN1 (management) and added (Untagged) to VLAN106. Ports g13 &amp; g14 were given PVID of 106. A laptop connected to g13 or g14 gets no IP address and if I manually set the laptop IP address to the same 10.0.0.x subnet it cannot ping anything or reach the web.&nbsp;I tried to set a VLAN routing address but no matter what I pick I get an alert: "IP Address/Netmask entered conflicts with the configured IP Address/Netmask of the service port or a router interface".&nbsp;I've spent 2 days trying all sorts of settings and reading the forums but I'm totally stuck so please any advice would be gratefully appreciated.&nbsp;Daz.&nbsp;&nbsp;&nbsp;

DaneA · Answer

@darrencole,&nbsp;Welcome to the community! 🙂&nbsp;The IP address of the GC728XP must be on subnet that is different from the subnet of the VLANs. &nbsp;It is because if you assign a VLAN Interface IP Address that is on the same subnet as with the IP Address of the switch, it will result to an error that says: "IP Address/Netmask entered conflicts with the configured IP Address/Netmask of the service port or a router interface".&nbsp;With regard to Inter-VLAN Routing, let me share the articles below and these might help as reference guides:&nbsp;VLAN Routing on Smart Switches&nbsp;VLAN Routing on a NETGEAR Smart Switch&nbsp;How do I set up one or more VLANs between a NETGEAR ProSAFE firewall and a smart switch?&nbsp;&nbsp;Regards,&nbsp;DaneANETGEAR Community Team

darrencole · Answer

Thanks DaneA for the response. I am still getting nowhere!

So attached is the diagram. Prior to trying VLANs computer A, B, C all got issued IP addresses and work to each other and had access to the web with no configuration.

I do not want ANY inter VLAN connectivity, I just want computer A & B to be on a VLAN for privacy and have access to the web which they do not. In fact B can ping A, but A cannot ping B. A works fine (no VLAN).

I have setup the VLAN as per knowledge base articles. VLAN 106 is on a completely different subnet as per your advice - what am I missing? Is it a route I need?

Many thanks in advance.

Daz

DaneA · Answer

darrencole,
&nbsp;
From the network diagram you have attached, it seems that your modem is a modem-router combo. &nbsp;About your goal to have the devices connected to VLAN 106 to have internet access, VLAN 106 needs to have its own DHCP server. &nbsp;Is your modem-router VLAN capable wherein it has the option to create another DHCP server for VLANs? &nbsp;
&nbsp;
As reference guide, kindly check this old article below that shows how VLANs are configured on both firewall router and a NETGEAR Smart Switch (like the GC728XP) that are directly connected to each other:
&nbsp;
How do I set up one or more VLANs between a NETGEAR ProSAFE firewall and a smart switch?
&nbsp;
Regards,
&nbsp;
DaneA
NETGEAR Community Team

darrencole · Answer

Thank you again DaneA! I setup a network identical to the one in your 'VLAN Routing on Smart Switches' guide.&nbsp;It's a crappy modem-combo that has a DHCP server but that isn't an issue - static IP addresses are fine. One of the steps in the guide is to create a default route on the switch to 192.168.1.1. After doing this I get the alert "The route will not take effect until a routing interface belonging to the same subnet as the next hop is created and activated". Problem is there is no router to do that.&nbsp;I have added a SonicWall TZ300 Firewall between the switch and the internet which does DHCP and can have static routes so I should be able to set the static route there?&nbsp;Daz

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GC728XP Cannot Get DHCP or VLANs to Work

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