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.
No problem! I always look at trying to keep the network as simple as possible because sometimes implementing routing just complicates the network and can also increase latencies between endpoints because of the processing the Layer3 devices need to do to move a packet from one point to another.
MDF = Main Distribution Frame - This is the main network closet/server room where each IDF will uplink to
IDF = Intermediate Distribution Frame - This is where each endpoint device will connect to
On the Master Switch (Layer3), make sure you've also created a VLAN ID 145 and have added this VLAN to the uplink port that you've trunked to the Layer2 switch. Both sides of the uplink (Layer3 and Layer2 switches) require VLAN ID 145 to be trunked so VLAN 145 traffic can pass through the uplink. Make sure you're able to ping 10.1.10.10 from the Layer2 switch after the trunk is created.
If the Layer2 switch is not routing, be sure to remove static routes (anything starting with "ip route"), the global "ip routing" command, and also the command "routing" from VLAN interfaces. I think an issue you're having is that the PowerConnect 6248 by default will try to route when a VLAN is created with the "routing" command specified. Essentially, you want the PowerConnect 6248 to act as if it were a PowerConnect 5448 which is only Layer2.
Remove ip helper-address commands from your VLANs and global configuration from your Layer2 switch. This command only needs to reside on the Layer3 device which I assume is acting as your core switch or MDF within your network. I would only add the "ip helper-address 10.1.10.10 dhcp" command to the VLAN that requires DHCP client requests to be forwarded to a DHCP server.
I always say to keep things simple especially if there is no requirement for intra-site routing. Have your core switch (MDF) do all your VLAN routing and each IDF simply will have an uplink that is trunked with the VLANs you want to pass traffic.
What command should I issue from the cli to remove the routing ? Also I do have dhcp client connected on the "layer 2" dell switch if I remove the ip-helper line how will they find the dhcp server? Are they gonna find it by going to the trunk and grab it from the layer 3 core ?
Thanks for the information, very helpfull. I wanted to have the setup that way from the beginning ( 1 layer 3 device and 1 layer 2) but it seem my config were badly done from start. One more newbie question, what does MDF ans IDF stand for ?
In order to enable routing for a specific VLAN you would enter the VLAN interface in this case VLAN 10.
console# config
console(config)# interface vlan 10
console(config-if-vlan10)# routing (enable routing for VLAN 10)
console(config-if-vlan10)# ip address 172.16.1.1 (set IP address for VLAN to route) (this would be the gateway address of any device connected to the VLAN)
randy_kuga
9 Posts
1
January 30th, 2012 13:00
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.
randy_kuga
9 Posts
1
January 30th, 2012 14:00
No problem! I always look at trying to keep the network as simple as possible because sometimes implementing routing just complicates the network and can also increase latencies between endpoints because of the processing the Layer3 devices need to do to move a packet from one point to another.
MDF = Main Distribution Frame - This is the main network closet/server room where each IDF will uplink to
IDF = Intermediate Distribution Frame - This is where each endpoint device will connect to
randy_kuga
9 Posts
0
January 30th, 2012 12:00
On the Master Switch (Layer3), make sure you've also created a VLAN ID 145 and have added this VLAN to the uplink port that you've trunked to the Layer2 switch. Both sides of the uplink (Layer3 and Layer2 switches) require VLAN ID 145 to be trunked so VLAN 145 traffic can pass through the uplink. Make sure you're able to ping 10.1.10.10 from the Layer2 switch after the trunk is created.
If the Layer2 switch is not routing, be sure to remove static routes (anything starting with "ip route"), the global "ip routing" command, and also the command "routing" from VLAN interfaces. I think an issue you're having is that the PowerConnect 6248 by default will try to route when a VLAN is created with the "routing" command specified. Essentially, you want the PowerConnect 6248 to act as if it were a PowerConnect 5448 which is only Layer2.
Remove ip helper-address commands from your VLANs and global configuration from your Layer2 switch. This command only needs to reside on the Layer3 device which I assume is acting as your core switch or MDF within your network. I would only add the "ip helper-address 10.1.10.10 dhcp" command to the VLAN that requires DHCP client requests to be forwarded to a DHCP server.
I always say to keep things simple especially if there is no requirement for intra-site routing. Have your core switch (MDF) do all your VLAN routing and each IDF simply will have an uplink that is trunked with the VLANs you want to pass traffic.
cividan
1 Rookie
•
16 Posts
0
January 30th, 2012 13:00
What command should I issue from the cli to remove the routing ? Also I do have dhcp client connected on the "layer 2" dell switch if I remove the ip-helper line how will they find the dhcp server? Are they gonna find it by going to the trunk and grab it from the layer 3 core ?
cividan
1 Rookie
•
16 Posts
0
January 30th, 2012 13:00
Thanks for the information, very helpfull. I wanted to have the setup that way from the beginning ( 1 layer 3 device and 1 layer 2) but it seem my config were badly done from start. One more newbie question, what does MDF ans IDF stand for ?
Thanks !
rdlafleur
20 Posts
0
October 16th, 2012 00:00
I can't figure out how to get vlan routing enabled via CLI. Your config has an the following:
vlan routing 30 1
...
Can you provide a CLI example to get this vlan routing statement to appear in my config?
DELL-Willy M
802 Posts
0
October 16th, 2012 10:00
In order to enable routing for a specific VLAN you would enter the VLAN interface in this case VLAN 10.
console# config
console(config)# interface vlan 10
console(config-if-vlan10)# routing (enable routing for VLAN 10)
console(config-if-vlan10)# ip address 172.16.1.1 (set IP address for VLAN to route) (this would be the gateway address of any device connected to the VLAN)
Hope this helps,
Keep us updated if you can.