To remove global IP routing, type this command from the enable prompt. no ip routing To remove routing per VLAN, type these commands. interface vlan # (in the place of the # sign, type the VLAN ID) no routing If the DHCP Server and Client Computers are connected to the same VLAN, the trunk port will allow forwarding of DHCP requests to the DHCP Server.  If the DHCP Server and Client Computers are connected to two separate VLANs, then yes the trunk port from the Layer2 switch will communicate with the Layer3 device but only if you have routing configured on your Layer3 device.  The Layer3 device will act as the bridge between each VLAN. The cleanest set up is to have one Layer3 device in the MDF act as your VLAN router for LAN traffic.  The other switches located in IDFs should communicate via a trunk.  Make sure the PC62XX does not perform any routing or you will be forced to create static routes or use a dymanic routing protocol for the two Layer3 devices to communicate. The PC62XX acting only as a Layer2 device only needs to trunk VLANs that it wants to pass to the PC62XX that is acting as the Layer3 device.  The Layer3 device will do all inter-VLAN routing.
Hi all, I have a Dell 6248 switch in layer 2 mode and I try to add a new vlan and have it relay dhcp to my server. That switch is connected with a trunk port to my master switch that does the layer 3 routing. I already have other vlan that work ok via the trunk port so i can set port on any switch to a vlan and they talk ok. the problem is when I add a new vlan they don't talk so I might have missed something obvious as this vlan thing is still pretty new to me.  I created the vlan on the master switch and it can talk to other vlan device located on the master switch but it cannot talk to anything on the dell switch so I'm guessing there is a problem on my vlan creation on the dell swtch so if anyone would provide me a step by step guide to creating a new vlan (ID 145), adding that vlan to the trunk port (1g/45) and enabling DHCP relay with address 10.1.10.10 that might help me figure out the problem I have.  Thanks !  Here is my running config if it may help.  Dell6248#show running-config!Current Configuration:!System Description "PowerConnect 6248, 3.3.1.10, VxWorks 6.5"!System Software Version 3.3.1.10!Cut-through mode is configured as disabled!configurevlan databasevlan 10,20,30,40,50,70,145,180vlan routing 30 1vlan routing 50 2vlan routing 180 3vlan routing 10 4vlan routing 70 5vlan routing 40 6vlan routing 20 7vlan routing 145 8exithostname "Dell6248"sntp server 10.1.10.10 priority 2clock summer-time recurring USA zone "EDT"clock timezone -5 minutes 0 zone "EST"stackmember 1 2exitip address 10.1.2.2 255.255.255.0ip default-gateway 10.1.2.3ip domain-name oculab.localip name-server 10.1.10.10no ipv6 enableip routingip route 0.0.0.0 0.0.0.0 10.1.20.3ip helper-address 10.1.10.10interface vlan 10name "vlan10"routingbandwidth 10000ip helper-address 10.1.10.10ip local-proxy-arpip mtu 1500exitinterface vlan 20name "vlan20"routingip address 10.1.20.2 255.255.255.0bandwidth 10000ip helper-address 10.1.10.10ip mtu 1500no ip unreachablesexitinterface vlan 30name "Office Users"routingbandwidth 10000ip helper-address 10.1.10.10ip helper-address 10.1.10.10 dhcpip mtu 1500exitinterface vlan 40name "office computer"routingip helper-address 10.1.10.10ip helper-address 10.1.10.10 dhcpexitinterface vlan 50name "Production"routingbandwidth 10000ip helper-address 10.1.10.10ip mtu 1500exitinterface vlan 70name "Printer"routingip helper-address 10.1.10.10exitinterface vlan 145name "Innova"routingexitinterface vlan 180name "Office Wireless"routingip helper-address 10.1.10.10exitusername "admin" password 1510c0828bb8c2f024d788a7d17bc8a0 level 15 encrypteddhcp l2relaydhcp l2relay vlan 1,10-100,145,180dhcp l2relay circuit-id vlan 10,20,30,40,50,70,145,180!interface ethernet 1/g1switchport access vlan 10exit!interface ethernet 1/g2switchport access vlan 10exit!interface ethernet 1/g3switchport access vlan 10exit!interface ethernet 1/g4switchport access vlan 10exit!interface ethernet 1/g5switchport access vlan 10exit!interface ethernet 1/g6switchport access vlan 10exit!interface ethernet 1/g7switchport access vlan 10exit!interface ethernet 1/g8switchport access vlan 10exit!interface ethernet 1/g9switchport access vlan 10exit!interface ethernet 1/g10switchport access vlan 10exit!interface ethernet 1/g11switchport access vlan 10exit!interface ethernet 1/g12switchport access vlan 10exit!interface ethernet 1/g13dhcp l2relayswitchport access vlan 10exit!interface ethernet 1/g14switchport access vlan 10exit!interface ethernet 1/g15switchport access vlan 10exit!interface ethernet 1/g16switchport access vlan 10exit!interface ethernet 1/g17switchport access vlan 10exit!interface ethernet 1/g18switchport access vlan 10exit!interface ethernet 1/g19switchport access vlan 50exit!interface ethernet 1/g20switchport access vlan 10exit!interface ethernet 1/g21switchport access vlan 20exit!interface ethernet 1/g22switchport access vlan 30exit!interface ethernet 1/g23switchport access vlan 40exit!interface ethernet 1/g24switchport access vlan 50exit!interface ethernet 1/g25switchport access vlan 70exit!interface ethernet 1/g26switchport access vlan 180exit!interface ethernet 1/g27switchport access vlan 50exit!interface ethernet 1/g28switchport access vlan 50exit!interface ethernet 1/g29switchport access vlan 145exit!interface ethernet 1/g30switchport access vlan 50exit!interface ethernet 1/g31switchport access vlan 50exit!interface ethernet 1/g32switchport access vlan 50exit!interface ethernet 1/g33switchport access vlan 50exit!interface ethernet 1/g34switchport access vlan 50exit!interface ethernet 1/g35switchport access vlan 50exit!interface ethernet 1/g36interface ethernet 1/g36switchport access vlan 50exit!interface ethernet 1/g37switchport access vlan 50exit!interface ethernet 1/g38switchport access vlan 50exit!interface ethernet 1/g41switchport access vlan 40exit!interface ethernet 1/g43switchport mode trunkswitchport trunk allowed vlan add 10,20,30,40,50,70,180exit!interface ethernet 1/g44switchport access vlan 180exit!interface ethernet 1/g45switchport mode trunkswitchport trunk allowed vlan add 10,20,30,40,50,70,145,180exit!interface ethernet 1/g46switchport access vlan 20exit!interface ethernet 1/g47switchport access vlan 30exit!interface ethernet 1/g48switchport access vlan 30exit!interface port-channel 1switchport access vlan 10exit!interface port-channel 2switchport access vlan 10exit!interface port-channel 3switchport access vlan 10exit!interface port-channel 4switchport access vlan 10exit!interface port-channel 5switchport access vlan 10exit!interface port-channel 6switchport access vlan 10 
Powerconnect 6248 adding new vlan with dhcp relay