2 LANS one printer

[paristotle]

I have 2 LANS each with their own gateway, and ISP that need to share a printer. LAN 1 172.16.3.X and LAN2 172.16.4.x. If I patch a port from a switch on LAN 1 to a switch on LAN 2 then DHCP requests would travel across and networks would become mixed. I need to share a printer only and keep the networks separate . If I allow tagged traffic only from one switch to the other could a effectively eliminate DHCP requests from coming across?

 

[onetech4all]

I was thinking that if the printer has a NIC card and a parallel port, you can use a parallel print server, connect the NICs to individual LANs and assign manual IP addresses to each NIC. In theory should work.

 

[paristotle]

Thanks for your reply. That's a great idea. The printer has only a USB port. I've had limited success with USB print servers recognizing and supporting USB printers.

I tried creating a static route between the two routers. It worked, but DHCP requests still traveled across. I was wondering if it was because the routers don't support RIP or OSPF. How do I keep the DHCP requests to one subnet? Hmmmm
I think I may have to resort to getting them a load balancing router and VLANing the two sub nets. The current routers don't support RIP.

 

[Martyn]

My old company used to manufacture printers that had embedded XP controllers. We used to bind two ip addresses(one on each subnet) to the nic in the controller and the 2 LANs could both print and that was the only connections between the two networks as far as I knew.

 

[paristotle]

Do they make the print servers separately?

 

[Martyn]

Do they make the print servers separately?

No these were controllers specifically for their own printer.

 

[onetech4all]

How do I keep the DHCP requests to one subnet? Hmmmm

- see if this link helps you http://www.serverwatch.com/tutorials/article.php/2193031. You can also assign static IP addresses on one of the subnets if you think it helps you.

 

[johnrobert]

Might be easier to buy another cheap printer

 

[drpcfix]

We did this with a workstation as the print server, put a workstation on both networks - you can have both IP addresses/networks on a single ethernet adapter in Windows/Mac/Linux/etc - have that machined hooked up to the printer and share it -

Now people on both networks can connect to that workstation, and therefore the printer

Not fun!

 

[glricht]

We did this with a workstation as the print server, put a workstation on both networks - you can have both IP addresses/networks on a single ethernet adapter in Windows/Mac/Linux/etc - have that machined hooked up to the printer and share it -

Now people on both networks can connect to that workstation, and therefore the printer

Not fun!

Back when I was in the corporate world, we failed a security audit because we had this same setup. The workstation sat on both networks and, according to the security auditors, could be used for people on one network to access data on the other network, defeating the entire purpose of network separation. The simplest solution was to get a 2nd printer, which we did.

 

[Long Time Tech]

VLANs should stop broadcast unless you have two dumb switches. What hardware are you using for the switch router?