Is this VLAN and Routing setup possible?

seth_turner_04 · 08-30-2007, 09:04 AM

Not sure if this should be here or in general networking so move if need be.

I have a Cisco 1000 router that has a 10.30.x.x subnet on it's ethernet side. On the serial interface, it has a VLAN from another school building with a 10.40.x.x subnet coming in over a T1 line. The 10.40.x.x VLAN is setup on an Allied Telesyn Layer 3 switch.

We have some computers that monitor our AC equipment that we need to have on the outside of our private network. There are three of the computers on the 10.30.x.x subnet and one on the 10.40.x.x subnet. Is it possible to setup a vlan with a 172.16.x.x address on the Layer 3 switch that comes in over the T1 line and have the router send out the 172.16.x.x packets on to our network?

The three on our physical network here in the high school can communicate with each other when we assigned them 172.16.x.x ip's. We just can't get the one on the other side of the router and separated by the T1 line to communicate.

We have a Border Manager server as our proxy and we have installed another network card with a 172.16.x.x ip to handle the allow and deny settings for accessing the computers over the internet.

Teknyk · 09-06-2007, 08:37 AM

seth, You really haven't provided enough information to answer this with any certainty.

In a general sense...
If the router thinks that the 172.16.x.x network is only connected off the ethernet interface, it will never send anything destined for that network out of the serial interface.

Your data will need a path back also so the same thing applies on the other side.
In nutshell, you will need that Vlan on both ends and the routers will need to know about them.

efuenteso · 09-11-2007, 07:58 PM

set, try to place a fisical layer of your network and put some ip adress over it, it would be easier to get an idea what do u want to get....

Regards, Efox

seth_turner_04 · 09-12-2007, 08:02 AM

thanks guy and sorry for not being better detailed about the situation. I have gotten the routing part taken care of. Now I just have to get the VLAN's setup within the building without breaking DHCP like I did the first time.

08-30-2007, 09:04 AM	#1 (permalink)
seth_turner_04 Registered User Join Date: Sep 2006 Location: Missouri Posts: 83 OS: XP Pro SP3, Vista	Is this VLAN and Routing setup possible? Not sure if this should be here or in general networking so move if need be. I have a Cisco 1000 router that has a 10.30.x.x subnet on it's ethernet side. On the serial interface, it has a VLAN from another school building with a 10.40.x.x subnet coming in over a T1 line. The 10.40.x.x VLAN is setup on an Allied Telesyn Layer 3 switch. We have some computers that monitor our AC equipment that we need to have on the outside of our private network. There are three of the computers on the 10.30.x.x subnet and one on the 10.40.x.x subnet. Is it possible to setup a vlan with a 172.16.x.x address on the Layer 3 switch that comes in over the T1 line and have the router send out the 172.16.x.x packets on to our network? The three on our physical network here in the high school can communicate with each other when we assigned them 172.16.x.x ip's. We just can't get the one on the other side of the router and separated by the T1 line to communicate. We have a Border Manager server as our proxy and we have installed another network card with a 172.16.x.x ip to handle the allow and deny settings for accessing the computers over the internet.

09-06-2007, 08:37 AM	#2 (permalink)
Teknyk Registered User Join Date: Aug 2007 Posts: 47 OS: Win2k3,XP,Linux	Re: Is this VLAN and Routing setup possible? seth, You really haven't provided enough information to answer this with any certainty. In a general sense... If the router thinks that the 172.16.x.x network is only connected off the ethernet interface, it will never send anything destined for that network out of the serial interface. Your data will need a path back also so the same thing applies on the other side. In nutshell, you will need that Vlan on both ends and the routers will need to know about them.

09-11-2007, 07:58 PM	#3 (permalink)
efuenteso Registered User Join Date: Sep 2007 Posts: 3 OS: xp	Re: Is this VLAN and Routing setup possible? set, try to place a fisical layer of your network and put some ip adress over it, it would be easier to get an idea what do u want to get.... Regards, Efox

09-12-2007, 08:02 AM	#4 (permalink)
seth_turner_04 Registered User Join Date: Sep 2006 Location: Missouri Posts: 83 OS: XP Pro SP3, Vista	Re: Is this VLAN and Routing setup possible? thanks guy and sorry for not being better detailed about the situation. I have gotten the routing part taken care of. Now I just have to get the VLAN's setup within the building without breaking DHCP like I did the first time.