How to use Synergy between local LAN and VPN connected PCs

[Jean-Pierre Masse]

I'm trying to see if there is a way to make my Synergy server laptop (MAC Book Pro), on my Home network, connect to my company PC also on the same network except, the Cisco client VPN is connected to my Company.

 

It seem my company do not permit to enable 2 network connection, VPN use the wireless one but disable the physical connection, so I can't enable it.

 

Can we use the Synergy with Bluetooth, USB or other way?

 

What will be the performance if I try to do it through the internet?

 

Thanks in advance for your support.

Jean-Pierre Masse

QC

[Tapio Luukkanen]

I'm successfully using a similar setup with an Ubuntu Synergy server and Windows 8 Synergy client.

 

The Windows client workstation is connected to 1-3 different VPN networks for my work.

 

You need to ensure that your VPN client software can be configured to allow local LAN access so that it can reach to your MAC.

[Micro]

I'm using a Mac as my server. Pc as my extended setup. My mac is connecting to a L2TP VPN and funnelling all traffic. I am still able to use synergy to a Windows 10 PC connected to the same local network not on the VPN.

 

I am using the hard coded server IP on my windows machine pointing to my Mac server. If that helps.

[Jonathan Sparks]

It takes a little work, but it is possible to use Synergy over VPN without split-tunneling. Here is what I did.

 

1) Register yourself a free (or paid if you don't want 30-day nags) dynamic DNS address (DDNS) from a place like dynDNS or no-ip

2) Register for the Pro version of Synergy to get that sweet, sweet SSL security. You're going to be opening some pin holes, so best to keep the connection secure while in transit

3) Select a non-default port for Synergy to use - again security precaution

 

From you home network router:

4) Create a DHCP reservation or assign a static IP for your server system

5) Create a port forwarding rule on the router that will forward all traffic destined for the port you determined in step 3 to the IP to determined in step 4 (source should be any IP, any port)

 

From Server system

6) Install Synergy if you haven't already done so, select server, and register your Pro key from step 2

7) On the Settings menu, enter the port number to determined in step 3, check the "Use SSL Security" box and click OK

8) Click Configure Server and then add your client screens as you normally would

 

From home router or server system

9a) If router supports automatic dynamic DNS updates, configure your router to update the address you registered in step 1 so your home external IP is tied to your DDNS address

-or-

9b) Install the DNS update client from the service used in step 1 so your home external IP is tied to your DDNS address

 

From your client system(s)

10) Install Synergy and select Client

11) For "Server IP," enter the DDNS address you created in step 1 (don't use auto config)

12) Make sure to set the same port number from step 3 in the Settings screen

13) Watch the magic happen

 

I think that about covers it...

Edited November 29, 2016 by Guest

[Ryan1491393327]

^^^ that's pretty smart. VPN's that don't allow split tunnels are just downright stupid.

[Jonathan Sparks]

^^^ that's pretty smart. VPN's that don't allow split tunnels are just downright stupid.

 

You actually want split tunneling disabled. When it is enabled, you are creating a link between an unsecured external network and an secured internal network. That is a man-in-the-middle attack waiting to happen. By disabling, you force all traffic through secured and monitored appliances.

 

Yeah, it sucks for people who work from home a lot (like myself), but I think the increased security is worth the hassle...plus I get to come up with creative solutions so I can still work. I get around it by have two systems, one on VPN and one not and using Synergy with SSL enabled to administrate them both simultaneously. If I need to move files between them or print something, I use iDrive (https://www.idrive.com/idrive/deals/pd/dgtlsparks) because I can define a custom 256-bit AES key (I own my data, not true for Google Drive and Dropbox) and then use their Sync service to move the files. Drop a file in a folder on one system and it appears in a folder on my other system.

[Tyler Chaves]

It takes a little work, but it is possible to use Synergy over VPN without split-tunneling. Here is what I did.

 

1) Register yourself a free (or paid if you don't want 30-day nags) dynamic DNS address (DDNS) from a place like dynDNS or no-ip

2) Register for the Pro version of Synergy to get that sweet, sweet SSL security. You're going to be opening some pin holes, so best to keep the connection secure while in transit

3) Select a non-default port for Synergy to use - again security precaution

 

From you home network router:

4) Create a DHCP reservation or assign a static IP for your server system

5) Create a port forwarding rule on the router that will forward all traffic destined for the port you determined in step 3 to the IP to determined in step 4 (source should be any IP, any port)

 

From Server system

6) Install Synergy if you haven't already done so, select server, and register your Pro key from step 2

7) On the Settings menu, enter the port number to determined in step 3, check the "Use SSL Security" box and click OK

8) Click Configure Server and then add your client screens as you normally would

 

From home router or server system

9a) If router supports automatic dynamic DNS updates, configure your router to update the address you registered in step 1 so your home external IP is tied to your DDNS address

-or-

9b) Install the DNS update client from the service used in step 1 so your home external IP is tied to your DDNS address

 

From your client system(s)

10) Install Synergy and select Client

11) For "Server IP," enter the DDNS address you created in step 1 (don't use auto config)

12) Make sure to set the same port number from step 3 in the Settings screen

13) Watch the magic happen

 

I think that about covers it...

 

I am attempting the process on a system with Cisco AnyConnect VPN. Followed your steps but having issues with the client not wanting to connect. Using the hostname to connect, getting error:

WARNING: failed to connect to server: Timed out.

 

No message comes up on the server, however. I can check the port I forwarded using portchecktool.com on my external IP, and it detects the service is open. Not sure what could be causing it. The hostname is properly registered using the tool offered from no-ip to my external IP address.

 

EDIT: Just to check, issue does occur with the VPN both enabled or disabled. With the VPN disabled, I can connect to the server with the local IP address.

[Jonathan Sparks]

 

I am attempting the process on a system with Cisco AnyConnect VPN. Followed your steps but having issues with the client not wanting to connect. Using the hostname to connect, getting error:

WARNING: failed to connect to server: Timed out.

 

No message comes up on the server, however. I can check the port I forwarded using portchecktool.com on my external IP, and it detects the service is open. Not sure what could be causing it. The hostname is properly registered using the tool offered from no-ip to my external IP address.

 

EDIT: Just to check, issue does occur with the VPN both enabled or disabled. With the VPN disabled, I can connect to the server with the local IP address.

 

Okay, this sounds like a DNS resolution issue to me - let's try a couple tests.

 

With VPN disabled, from your client machine (assuming ICMP is enabled for the external interface of the router):

 

Is nslookup or dig resolving the dynamic DNS name correctly (is it returning your external IP)?

Are you able to ping your server via the dynamic DNS name?

Are you able to telnet to the server port via the dynamic DNS name?

Will Synergy connect if you use the external IP for your server?

Is the port forwarding counter increasing on your router when you are attempting the connections?

[Tyler Chaves]

Okay, this sounds like a DNS resolution issue to me - let's try a couple tests.

 

With VPN disabled, from your client machine (assuming ICMP is enabled for the external interface of the router):

 

Is nslookup or dig resolving the dynamic DNS name correctly (is it returning your external IP)?

Are you able to ping your server via the dynamic DNS name?

Are you able to telnet to the server port via the dynamic DNS name?

Will Synergy connect if you use the external IP for your server?

Is the port forwarding counter increasing on your router when you are attempting the connections?

 

1. It does resolve correctly showing my external IP

2. Yes, off the VPN only.

3. Yep, ablet to telnet using adminkit.net

4. It does not, the same issue occurs using the IP.

5. Can't seem to locate any sort of counter, I am checking logs but no luck at the moment.

 

Tested with another system, same exact issue so definitely unrelated to the VPN, but the DNS resolves correctly from what I can see so far. Lost at this point.

 

EDIT: For now, I have employed a workaround that fulfills my needs at the moment. Thanks for the response to my issue, if you have more ideas for troubleshooting and feel like posting, I may refer back to this later and other members may find it useful. Thanks again

[jmcfadden]

Jonathan Sparks,  Pure genius!  I have been hunting for a solution to the "Synergy with a system on VPN" for months...just happened to get the google search phrase correct to see this thread.  I am now enjoying a Synergy Shared KBD and Mouse across my two systems with one on VPN.  

Thanks so much for this

[Matt Keyes]

I know this is an older post, but is this still a viable solution?  I've gone through the steps as suggested and when I connect my VPN it drops my synergy connection and I can no longer lookup my DDNS hostname.

Any suggestions?

[Jonathan Sparks]

I haven't upgraded to 2.0 yet, which is supposed to have a cloud-based broker, but I don't know if that is live yet.

It could be that dynamic DNS sites are being blocked by the firewall once connected to VPN (some services block them or see them a parked domains). Might want to try it by IP address only first, since the DDNS portion is just to handle IP changes on your home ISP.

[FJGold]

Is there any way to make this work with Synergy2 yet?

[husic100001001]

On 11/23/2016 at 7:37 PM, Jonathan Sparks said:

It takes a little work, but it is possible to use Synergy over VPN without split-tunneling. Here is what I did.

 

1) Register yourself a free (or paid if you don't want 30-day nags) dynamic DNS address (DDNS) from a place like dynDNS or no-ip

2) Register for the Pro version of Synergy to get that sweet, sweet SSL security. You're going to be opening some pin holes, so best to keep the connection secure while in transit

3) Select a non-default port for Synergy to use - again security precaution

 

From you home network router:

4) Create a DHCP reservation or assign a static IP for your server system

5) Create a port forwarding rule on the router that will forward all traffic destined for the port you determined in step 3 to the IP to determined in step 4 (source should be any IP, any port)

 

From Server system

6) Install Synergy if you haven't already done so, select server, and register your Pro key from step 2

7) On the Settings menu, enter the port number to determined in step 3, check the "Use SSL Security" box and click OK

8) Click Configure Server and then add your client screens as you normally would

 

From home router or server system

9a) If router supports automatic dynamic DNS updates, configure your router to update the address you registered in step 1 so your home external IP is tied to your DDNS address

-or-

9b) Install the DNS update client from the service used in step 1 so your home external IP is tied to your DDNS address

 

From your client system(s)

10) Install Synergy and select Client

11) For "Server IP," enter the DDNS address you created in step 1 (don't use auto config)

12) Make sure to set the same port number from step 3 in the Settings screen

13) Watch the magic happen

 

I think that about covers it...

Hi J.P.

 

I really hope you read this, or anyone else in this old thread, to help me implement your work around. I'm stuck & do not understand what to do at...

3) Select a non-default port for Synergy to use - again security precaution

Also all the Router stuff...

I have a 2011 Mac Mini i7 quad-core 8gig Desktop... a 2011 Macbook Pro i7, quad-core 4gig Laptop... & a TP-LINK: TL-WR741ND Router.

I have ExpressVPN on both computers but would like it mainly for the internet on my Mac Mini.

I have so far put Synergy Pro 1 on both machines, making the Laptop the 'server' & the Desktop the 'client'. That I have working at least, lol

I'm out of my depth here guys & would truly appreciate anyones help here, thanks ")

- Harley, NZ

Edited June 20, 2018 by husic100001001
wording, spelling

[husic100001001]

9 minutes ago, husic100001001 said:

Hi J.P.

 

I really hope you read this, or anyone else in this old thread, to help me implement your work around. I'm stuck & do not understand what to do at...

3) Select a non-default port for Synergy to use - again security precaution

Also all the Router stuff...

I have a 2011 Mac Mini i7 quad-core 8gig Desktop... a 2011 Macbook Pro i7, quad-core 4gig Laptop... & a TP-LINK: TL-WR741ND Router.

I have ExpressVPN on both computers but would like it mainly for the internet on my Mac Mini.

I have so far put Synergy Pro 1 on both machines, making the Laptop the 'server' & the Desktop the 'client'. That I have working at least, lol

I'm out of my depth here guys & would truly appreciate anyones help here, thanks ")

- Harley, NZ

forgot to add I have created a ww.dyndns.org account & choose that one as it, along with ww.no-ip.com & one other, are included in my routers DynamicDNS options! It is however prompting me to purchase at US$55 annual which I wont do unless I can make this thing actually work

[WarriorPaul]

So I did what Jonathan Sparks said and I still cannot get it to work. It does all work with the dns name if I am not on my vpn but if I enable my vpn it stop working with the timeout error. I tried on maybe different ports also. 

I have my computer that is on the vpn as my client and the computer that is not on the vpn as the server. Is this right?

[glenm]

Just for completeness, and not to take away from Jonathan Sparks' clever solution ... 

If you use a static IP address at home (as I do), then steps 1 and 9 could probably be omitted, and in step 11 use your home's public IP address.  Depending on your ISP, static IP addresses are more or less available and not all that expensive.

[Marcepan]

On 23/11/2016 at 7:37 AM, Jonathan Sparks said:

It takes a little work, but it is possible to use Synergy over VPN without split-tunneling. Here is what I did.

 

1) Register yourself a free (or paid if you don't want 30-day nags) dynamic DNS address (DDNS) from a place like dynDNS or no-ip

2) Register for the Pro version of Synergy to get that sweet, sweet SSL security. You're going to be opening some pin holes, so best to keep the connection secure while in transit

3) Select a non-default port for Synergy to use - again security precaution

 

From you home network router:

4) Create a DHCP reservation or assign a static IP for your server system

5) Create a port forwarding rule on the router that will forward all traffic destined for the port you determined in step 3 to the IP to determined in step 4 (source should be any IP, any port)

 

From Server system

6) Install Synergy if you haven't already done so, select server, and register your Pro key from step 2

7) On the Settings menu, enter the port number to determined in step 3, check the "Use SSL Security" box and click OK

8) Click Configure Server and then add your client screens as you normally would

 

From home router or server system

9a) If router supports automatic dynamic DNS updates, configure your router to update the address you registered in step 1 so your home external IP is tied to your DDNS address

-or-

9b) Install the DNS update client from the service used in step 1 so your home external IP is tied to your DDNS address

 

From your client system(s)

10) Install Synergy and select Client

11) For "Server IP," enter the DDNS address you created in step 1 (don't use auto config)

12) Make sure to set the same port number from step 3 in the Settings screen

13) Watch the magic happen

 

I think that about covers it...

Mate, just wanted to say how cool this solution is. Even if this thread is ancient and you may not see my reply, I am gonna leave one for others that are looking for VPN solution.

Just managed to get my work laptop working with VPN enabled, PulseSecure - totally not configurable. Work network refuses connection to LOADS of DDNS servers, but no-ip came to the rescue and I found one that is working. In addition, I have crappy Sagemcom router which was pain to configure, but thankfully supports port forwarding and dynamic DNS so all is good after all.

If Symless doesn't implement native VPN solution, this is my way to go from now (well, still need to test in proper work situation for stability).

Thanks again!

Edited March 14, 2020 by Marcepan

[Red313]

On 3/14/2020 at 4:26 PM, Marcepan said:

Mate, just wanted to say how cool this solution is. Even if this thread is ancient and you may not see my reply, I am gonna leave one for others that are looking for VPN solution.

Just managed to get my work laptop working with VPN enabled, PulseSecure - totally not configurable. Work network refuses connection to LOADS of DDNS servers, but no-ip came to the rescue and I found one that is working. In addition, I have crappy Sagemcom router which was pain to configure, but thankfully supports port forwarding and dynamic DNS so all is good after all.

If Symless doesn't implement native VPN solution, this is my way to go from now (well, still need to test in proper work situation for stability).

Thanks again!

Hi Marcepan,

I got Pulse Secure as well and its giving me a Timeout error when on VPN. It works without VPN. I'm wondering, what do you mean exactly by "no-ip" came to the rescue and you found a working DDNS server ? Which one is it ?

 

Thank you

[ecshsun]

Hi Marcepan,

After much frustration I found this thread and implemented the solution using the following setup:

• Server: Synergy Pro 1.13.1 Ubuntu
• Client: Synergy Pro 1.11.1 Windows
• Cisco AnyConnect VPN (on Ubuntu)
• No-IP DDNS
• Sagem WiFi Router (supports DHCP reservation, DDNS and port forwarding)

It works beautifully. Thank you for posting!

[infirstplace]

On 11/22/2016 at 11:37 PM, Jonathan Sparks said:

It takes a little work, but it is possible to use Synergy over VPN without split-tunneling. Here is what I did.

 

1) Register yourself a free (or paid if you don't want 30-day nags) dynamic DNS address (DDNS) from a place like dynDNS or no-ip

2) Register for the Pro version of Synergy to get that sweet, sweet SSL security. You're going to be opening some pin holes, so best to keep the connection secure while in transit

3) Select a non-default port for Synergy to use - again security precaution

 

From you home network router:

4) Create a DHCP reservation or assign a static IP for your server system

5) Create a port forwarding rule on the router that will forward all traffic destined for the port you determined in step 3 to the IP to determined in step 4 (source should be any IP, any port)

 

From Server system

6) Install Synergy if you haven't already done so, select server, and register your Pro key from step 2

7) On the Settings menu, enter the port number to determined in step 3, check the "Use SSL Security" box and click OK

8) Click Configure Server and then add your client screens as you normally would

 

From home router or server system

9a) If router supports automatic dynamic DNS updates, configure your router to update the address you registered in step 1 so your home external IP is tied to your DDNS address

-or-

9b) Install the DNS update client from the service used in step 1 so your home external IP is tied to your DDNS address

 

From your client system(s)

10) Install Synergy and select Client

11) For "Server IP," enter the DDNS address you created in step 1 (don't use auto config)

12) Make sure to set the same port number from step 3 in the Settings screen

13) Watch the magic happen

 

I think that about covers it...

Wow this tutorial was amazing. Thank you very much for taking the time to write it.

[Chris Hensley]

I struggled with this VPN set up Jonathan Sparks suggested however I did get it working.

Follow process to use Dynamic Dns if you want, I don't think its required.

If you are having issues it's probably the port you selected. VPN or firewall might have the Dynamic / Private port range turned off.

You might have to pick a port that is "Techinically" assigned to other services if you was using them or calling on them. 

For me it was definately a port issue. I ended up using port 8080 knowing it will be hard for vpn services to block that port without impacting web services. 

[Jongraphs]

Can’t You just set up port forwarding on 24800?

[Girl1der]

On 11/22/2016 at 10:37 PM, Jonathan Sparks said:

It takes a little work, but it is possible to use Synergy over VPN without split-tunneling. Here is what I did.

 

1) Register yourself a free (or paid if you don't want 30-day nags) dynamic DNS address (DDNS) from a place like dynDNS or no-ip

2) Register for the Pro version of Synergy to get that sweet, sweet SSL security. You're going to be opening some pin holes, so best to keep the connection secure while in transit

3) Select a non-default port for Synergy to use - again security precaution

 

From you home network router:

4) Create a DHCP reservation or assign a static IP for your server system

5) Create a port forwarding rule on the router that will forward all traffic destined for the port you determined in step 3 to the IP to determined in step 4 (source should be any IP, any port)

 

From Server system

6) Install Synergy if you haven't already done so, select server, and register your Pro key from step 2

7) On the Settings menu, enter the port number to determined in step 3, check the "Use SSL Security" box and click OK

8) Click Configure Server and then add your client screens as you normally would

 

From home router or server system

9a) If router supports automatic dynamic DNS updates, configure your router to update the address you registered in step 1 so your home external IP is tied to your DDNS address

-or-

9b) Install the DNS update client from the service used in step 1 so your home external IP is tied to your DDNS address

 

From your client system(s)

10) Install Synergy and select Client

11) For "Server IP," enter the DDNS address you created in step 1 (don't use auto config)

12) Make sure to set the same port number from step 3 in the Settings screen

13) Watch the magic happen

 

I think that about covers it...

Ok, I did all this and its working, thank you @Jonathan Sparks. My only issue now is on the remote computer (on VPN) , the mouse and keyboard response is super slow. :( 

[locuturus]

I tried a weird thing - disconnected my VPN, paired the work PC to the server (my gaming rig), and then reconnected the VPN on work PC. Presto! I can't explain why, but it's working...

Hope that helps someone...