Networking advice needed please. - Page 1
Forum section: electronics / general

author: funkyant
author_rank: Unknown
timestamp: November 13, 2016, 08:40:25 pm
content: I have a router with DHCP in ranges 192.168.52.X which is basically serving internet on an audio control network.I also have a TP Link TL-SG3424P managed PoE switch with no DHCP, all fixed IPs on 192.168.1.X which is for a separate lighting control network (ARTnet).These two networks are physically separate, however I need one of the PCs on the lighting network to have internet access. Obviously, it's on a different subnet, so even if I plug the router into the switch, the PC has no internet without changing its network settings, which then makes it unable to see the ARTnet nodes.Seems like there is an easy solution, however I do not really know how to do it.Suggestions very welcome.

author: 1xrtt
author_rank: Regular Contributor
timestamp: November 13, 2016, 09:30:42 pm
content: If you don't have a second NIC on the PC, a very crude way is to set up an additional IP address on the same interface, on the subnet 192.168.52.x, connecting the router on the TPLink switch.There are a few problems though: both IP address (on subnet 192.168.1.x and 192.168.52.x) must be statically configured, so you need to choose an unassigned IP on the DHCP pool.Also, you need to manually set the default route to the router's IP.- On Windows, go to Control Panel, open the IPv4 configuration on the interface, click on Advanced and on the IP Settings Tab, click on Add...- Add the default gateway, pointing to router's IP , but remove the default gateway that exists for subnet 192.168.1.x:I don't particularly like this setup, specially because of all security problems it may create, but it's a quick way to get what you want

author: Halcyon
author_rank: Unknown
timestamp: November 13, 2016, 09:31:07 pm
content: To do things properly, you really need a proper router (or something like a machine runningpfsense) to set up the routing you need with proper rules etc...Alternatively, check the admin page for your router (the one with the internet connection), even some consumer grade gear allows you to set up different VLANs. All you'd need to do is dedicate a port on that router for your 192.168.1.0 network and connect your lighting control switch to it. This would still allow you to keep the two networks separate.If that isn't possible, you could simply connect the switch to the router and configure your network adapter in the machine you want internet access on to have two IP configurations (in Windows: go to the TCP/IP settings > Alternate Configuration). That way, your lighting machine will have one network interface but with a 192.168.1.0 address and a 192.168.52.0 address simultaneously with their own gateway and DNS information. It's not ideal, but it's quick and dirty and should do the job. Just remember, if you join the two networks, any machine requesting an address via DHCP on your "lighting" network, will get one from the modem/router. But if you use statically assigned addresses anyway, this might not be a problem for you.Edit: 1xrtt was too quick for me. :-)

author: kripton2035
author_rank: Super Contributor
timestamp: November 13, 2016, 09:32:44 pm
content: on my mac, I can have 2 virtual networks on the same ethernet port, and so be able to address the both networks.on a linux machine I presume it is also possible.on a windows machine, I don't know ! (but I'm pretty sure you can)

author: funkyant
author_rank: Unknown
timestamp: November 13, 2016, 10:02:41 pm
content: Many thanks guys. I'm going to mess around with some of these ideas and report back.Ideally want to use only one Ethernet cable to the machine if possible. Only one NIC on the motherboard but a PCI card is certainly an option. Budget is not really an issue.

author: The Soulman
author_rank: Super Contributor
timestamp: November 13, 2016, 10:46:34 pm
content: At the theater where I work we've chosen to keep everything "mission critical" on separate static ip networks closed off to the rest off the world.Machines that also need to be connected to the internet i.e. the laptop of the sound operator who has non show related stuff to do in the brake isalso connected thru wifi to the guest network.If there isn't a apparent need to have www on your artnet (no working from home thru vpn) than I'd suggest get a third(wifi) network for the internet and connect the devices that only need it to it thru a second network adapter.You don't want a show stop just because anonymous had decided so..

author: Ampera
author_rank: Super Contributor
timestamp: November 13, 2016, 11:50:51 pm
content: Quote from: funkyant on November 13, 2016, 10:02:41 pmif budget isn't an issue, you can try using WLAN.I occasionally use it if I need to connect between my two home networks.

author: gnif
author_rank: Unknown
timestamp: November 14, 2016, 12:07:21 am
content: Personally I would get a router and configure it as a gateway to the rest of your network, even an old second hand WRT54GL or TP-Link would do the trick, something that OpenWRT is available for. This would both provide physical network separation and you could firewall the traffic between the two networks.I have done the same thing in the past when working on client's computers that were possibly infected, where I used an old PC running Linux to be a gateway and caching proxy for things like windows updates (back when you could cache these). If you don't mind messing around a bit, you could always get a RPi, even the first generation one if you have one laying about and plug a USB NIC into it for the other network.If you need any assistance in configuring a Linux gateway I would be more then happy to lend a hand.