Frequently Asked Question
Devices lose their IP address after I create a VLAN on a D-Link smart switch. Why?
QUICK ANSWER
Check VLAN membership, PVID and the complete route to the DHCP server. Creating a VLAN on a switch does not automatically create a router interface or DHCP service.
Applies to: D-Link smart managed switches supporting 802.1Q VLANs, including DGS-1100 V2. Menu names and routing features vary by model.
Work through these checks
- Record the intended VLAN ID, router/DHCP location and the switch ports used by the client and uplink. Keep one known-working management connection.
- For a normal untagged client, check that its access port is untagged in the intended VLAN and has the matching PVID. PVID classifies incoming untagged traffic; it does not replace VLAN membership.
- Check that uplinks carry the intended VLAN with matching tagging on both ends. The gateway must have the corresponding interface/subnet and an available DHCP scope or appropriate relay.
- Test one client/port before applying changes widely. After the configuration works, save it using the switch's persistent configuration control if required.
Confirm the result
The test client should receive the intended subnet, gateway and DNS settings and reach permitted destinations. Confirm that the management network still works.
Before going further: Do not remove the management VLAN or enable every VLAN on every port to work around a missing lease.
If you need help
Include these details in your ticket: Model/hardware revision, firmware, port diagram and redacted VLAN/PVID settings.
Updated 261107