Use LAN to interface Synergy while having WiFi connected to internet
Similar question and solution
I have LAN and WiFi connection, with the WiFi connected to internet and the LAN is simply connected via an Ethernet cable between two computers. I need to get Synergy working without compromising the WiFi internet. I've tried the solution above but couldn't seem to work. Both of the computer are running Windows XP.
Even setting the LAN IP to static and under the same subnet doesn't seem to work. Anyone with similar situation and got Synergy to work?
edit : Refined the question for clarity. Also, the computer are able to ping each other. Remote desktop can be accessed as well. I suspect the problem lies in Synergy's configuration.
Add the /32 address(es) of the other machine(s) to the routing table via the wired interface.
If I understand your question properly, you are looking to connect 2 computers together using an ethernet cable, and use that link to drive synergy. It will be important that your Wifi internet connection not be disrupted by the addition of this wired network.
If that is an accurate assessment of what you are looking to accomplish, then you would need to use a crossover cable to connect the 2 computers together. For the wired connection on each machine, you should assign a static IP that is in a different subnet than your wifi network. For example, if your Wifi network is on 192.168.X.X, then you should use 172.16.1.X for your wired network.
Once the wired network is configured, and you can ping between the 2 and your Wifi internet is still functional, then you should configure Synergy using the static IPs that you have assigned to the wired interfaces.
This should be Operating system agnostic.
There are a couple of drawbacks to this method however. The main one is that you will not be able to add an additional computer into the wired network without the additional of a switch. To be honest, you can pick up a used SOHO switch on-line for less than you will probably pay for the crossover cable at an electronic store.
Are your IP addresses in the same range (IE ethernet range is in 192.168.1.x and so is wireless) if so the wireless (and its gateway) might be "stealing" the traffic and not knowing how to get it back. To avoid this I would suggest running synergy on its own separate range. If your home network is 192.168.1.x let your wireless grab one of those, give the ethernet connections a manual address. Something in a different range like 2.x
Try pinging between the machines with the 2.x address to check connectivity. Then make sure you have the Client (computer with no keyboard/mouse) configured to use the server's 2.x address
A sample (redacted) config from my setup is here http://pastebin.com/R7zz5jfC
I'm not sure which OS you are using for your Synergy server and client, but this worked with Ubuntu 18.04 as my server and Windows 10 as my client.
Wired Connection
First connect your two computers with an Ethernet cable. If your network device was made in the last 10 years, there shouldn't be any need for a crossover cable. Any Ethernet cable should do. Modern network equipment should be able to detect and switch itself with no need for a crossover cable.
Configure the Server
Disable your IPv6 connection and set IPV4 to "Manual". Then configure your address, netmask, and DNS as shown below (or something similar). If your LAN usually uses an IP like 192.168.1.x, then you'll want to use a different set of numbers for the address (like how I used 169.254.40.x).
Before hitting Apply, make sure you check the box at the bottom that says "Use this connection only for resources on its network". Okay, now you can hit "Apply".
Configure the Client
Press the Windows key and the R key at the same time to open the Run box. Type ncpa.cpl and hit Enter. Right click on your ethernet connection and select Properties. Uncheck "Internet Protocol Version 6 (TCP/IPv6)". Then select "Internet Protocol Version 4 (TCP/IPv4)" and click the Properties button. Configure your address, netmask, and DNS as shown below. You'll want to make sure that the IP address is the same as the server's except for the last digit (I just incremented mine like an odometer), and make sure that the subnet mask and DNS are identical to the server's netmask and DNS. Yes, the nomenclatures are slightly different, but they are the same things.
Lastly, in the Synergy client's Server field, set the IP to address that you assigned your server in the "Configure the Server" section. In the example below, I have it set to "169.254.40.232".
You may need to toggle your connections on/off or start/stop the Synergy client to get the connections to reset, but otherwise you should be set. If this was helpful (I spent two days trying to figure all this out), please consider giving me an up-vote. Thank you!