Physically connect 2 separate networks and get them to email each other

You could add a NIC card to the computers so they are able to communicate with eachother. Another way is simply join them in a homegroup to eachother. That allows them to recongize either one and able to communicate. If you have a server have them join the domain and that will allow it as well.

They are 2 full blown domains. They each have their own exchange server and domain controllers. I prefer not to add nics, I want them to maybe be trusted but the dcs are already in place. maybe I could just connect domain a to domain b in a differnt vlan on router, then add both exchange servers to dns and see if they can ping then add an external domain to the exchange 2007 . I am not 100 percent sure.

Its 2 separate domains in the same bldg. There is only 1 main router on the bigger network. But on the main router I was going to create a new vlan for the smaller network and put their main switch in that vlan. Then ensure that they can ping across, then add the dns entries for the exchange server . Then add an external domain to the exchange server and pray that it works lol. Logically it sounds feasable but maybe I just think it will work.

yea that should surely work i would believe myself. I think that you only need 1 router on the big network since you have only 2 smaller dc's that you are dealing with. Since you only have a small workgroup you shouldnt have any problems with them communicating to eachother. Lol but yea i agree with computers a lot of times you just have to try and pray it works. Let me know if it doesnt and we can throw out some new crazy ideas :)

Hi JBell.  If you already have the router in place & the default routes on the servers, that helps.  You WILL need to set up conditional forwarding on the DNS servers on both sides.  If you have an Exchange server on each side then there is no configuration required directly on them. As a test you can log onto the mail server in Domain A & telnet on port 25 to the mail server in domain B. If you can open a session then you have connectivity.

Hit a road block. I was going to create a new vlan, with 10.1.1.0 as the network, 10.1.1.1 as the gw etc and add just several of the users to this new vlan just to test it out for connectivity then add dns entries to each dns server. BUT, the networks in which the exchange server is on are the same on both separate networks. For example, network A is 10.1.2.0 and for petes sake the test network which I want to connect to the main network, is also 10.1.2.0. Is there anywhere around this w/o re-iping one of the networks. They would be sharing the same router but different vlans.

do you have a dhcp server installed on there that way it can obtain them privately?
If you already do what you could do is subnet them so that they are spanning out

Oh wait, I could change the ip address of the exchange server to the 10.1.1.0 network and they should still be able to get to it as it is routeable. That way, the 2 exchange servers on the 2 different networks will be on different subnets.

yes exactly what i was implying

That's going to prove very complicated because you will need an additional interface on the router, will need to change all the TCP/IP settings on the Exchange server, possibly change your NAT or PAT settings, add another DNS zone for that range, put in a switch just for the Exchange server (or use a x-over cable to connect direct to router).  It also means that all your client-server email traffic on that subnet will have to traverse the router, adding to the load.
I've seen similar situations before, and the best practice is to plan & carefully execute an addressing change.  You also need to think ahead & plan for future interactions between the subnets.  How many servers & clients do you have on the smaller LAN?

The smaller lan is only 1 dc and 1 exchange server.

Since you have a very small network i dont think you will arise those probelms you may have to change a few settings and make sure they match up but you should have to change everything and apply a whole bunch of expenses

I have 1 interface left on the router in which I was going to connect that to the existing switch and create the additional vlan on the switch with that interface as the gw, would that work or would i need a completely new switch?

Nah you can use that on the same switch. You really only need that one switch unless you have more than a few networks on it. Adding more swtiches adds more labor and complications

OK I Am confusing mysef now. This is how the router and switch are set up:

On Main Router

interface FastEthernet0/0
ip address 10.0.1.1 255.255.255.0


On switch


interface vlan 1
ip address 10.0.1.2 255.255.255.0
exit
ip default-gateway 10.0.1.1   ????


So on 2nd interface it should be

interface FastEthernet0/1
ip address 10.0.2.1 255.255.255.0


switch
interface vlan 1
ip address 10.0.2.2 255.255.255.0
exit
ip default-gateway 10.0.1.1  ????? Would i not put a gw here?

Can their be 2 gw's on a switch?

yea gateways dont have to be on separate swtiches.

interface FastEthernet0/0
ip address 10.0.1.1 255.255.255.0


On switch


interface vlan 1
ip address 10.0.1.2 255.255.255.0
exit
ip default-gateway 10.0.1.1   ???? DO i have to put a gw here since this it is directly connecte to f0/0 which is the router interface?

And just set my gws on pcs etc to 10.0.1.1 which is the ip address of router interface?

The router interface should be 10.0.1.1

Right, my question is can I not put a default gw on the switch since both router interfaces are connecting directly to switch and I could just use the router interfaces as my gw on devices on the networks.

Yea you can do that...that will not do anything. That is basically what a router is.

OK, I was just able to try it out today. The switch can talk to the router but when i plug a pc into vlan2, it can not talk to router. I had to create a subinterface as I was out of L3 ports.


Router

interface fastethernet 0/0
ip addres 10.0.51.1 255.255.255.0
duplex auto
speed auto (this is the gw for my regular lan)

interface fastethernet0/0.10
ip address 10.0.52.1 255.255.255.0
(This is the new subnet I want to add)


Switch

Int vlan 1
10.0.51.4 255.255.255.0

int vlan 2
internal network
(no ip address assigned)


ip default-gateway 10.0.51.1


So, From the switch I can finally ping the router interfcae of 10.0.52.1, but when I put ports in vlan 2 I can not ping 10.0.52.1

Example POrt 8 is in vlan 2 on switch
ipconfig of pc
10.0.52.5
255.255.255.0
gw 10.0.52.1


But I can not ping 10.0.52.1 from pc.

Make sense?

Both lead me to my solution. I added another wic card, connected the router to another vlan in switch and it worked.