If this is not successful, repeat the test from the server VLAN.On the switch, you can specify the source address for a ping with the command ping from. If IP forwarding is enabled, verify that the DHCP server is reachable from the client VLAN.If this is not enabled, enable IP forwarding on both VLANs.

The output of show vlan should show an f flag for these VLANs.

If bootprelay is configured correctly, verify that IP forwarding is enabled on both the client and server VLANs.

If bootprelay is not configured, configure it pointing to the DHCP server.

On the router for the VLAN, check to see if bootprelay is enabled for both the client and server VLANs. Determine where routing is happening for the client's VLAN.If the client never sends a Request or Offer, ensure that DHCP is enabled on the client.Ĭase 2: DHCP Server and DHCP Client are in separate VLANs.If the DHCP server sees the Request or Offer come in, but does not respond, ensure that the DHCP scope is configured correctly.The syntax of this filter is bootp.hw.mac_addr =. In Wireshark, a display filter can be applied to view just DHCP traffic for one specific client. If the client is able to reach the DHCP server with a static IP address, take a packet capture on both the client and the DHCP server to determine where the DHCP process is breaking down.If this is correct on both ends, verify the VLAN configuration and tagging on all switches between the client and DHCP server. Repeat the troubleshooting from step 1 for the DHCP server. Is the test client able to ping the DHCP server? If not, there is a connectivity issue to the DHCP server. Configure the test client with a static IP address in the correct subnet.Is the client directly connected, or is there something else in between?.Is the VLAN tagging correct on the port?.Is the MAC address learned in the correct VLAN? If yes, skip to step 2.Find the port that this client is connected to, then run show fdb port.

Case 1: DHCP Server and DHCP Client are in the same VLAN

Wireshark capture filter dhcp