SonicWall DHCPD – Does Not Allocate Subnet Addresses

dhcpsonicwallsubnet

Why does my SonicWall fail to allocate DHCP addresses to my virtual subnet?

I am trying to configure our VoIP phones. I have configured our sonicwall TZ 215 to have two networks on the LAN:

  • Interface X0: 192.168.1.x
  • Interface X0:V10 10.100.10.x

I have configured DHCPD on the sonicwall to allocate a static address, 10.100.1.82, to a phone with a specific mac address connecting over the X0 physical interface.

This works fine, if the static DHCP entry on the SonicWall allocates the address to the 192.X network. However, when I configure the static DHCP entry to allocate a 10.x address on the virtual interface subnet, the Sonic Wall does not provide a DHCP response to the phone.

Thank you for your help!!

Here are a few config images:

Lease Scopes
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Network Diagram:
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Best Answer

You need to replace the switch with a managed switch that supports VLANs for this to work.

The Sonicwall X0 interface is configured as a trunk, with to VLANs: a "native" VLAN for untagged frames, and V10 for frames tagged with VLAN ID 10. Frames that arrive at the Sonicwall untagged come in at interface X0, and frames that are tagged with VLAN ID 10 come in at interface X0:V10.

The switch you have does not support VLANs. This means that it will send all traffic to the Sonicwall untagged. So regardless of what you configure on the IP Phone, traffic will arrive only on interface X0, and never on X0:V10.

In order for this to work, you would need to configure the switchports to the Sonicwall and to the IP Phones with an untagged "native" VLAN and a tagged VLAN 10. So you need to have a managed switch that supports VLANs instead of the unmanaged switch.

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