FG Knowledge Base - Firewalls

[JeffKnight]

If you own your own server (or vps) you can use OpenVPN using TAP interfaces (I haven't tried with TUN) as well with iptables like so:

iptables -t nat -A PREROUTING -d x.x.x.x -p tcp --dport 1802 -j DNAT --to-dest z.z.z.z:1802
iptables -t nat -A POSTROUTING -d z.z.z.z -p tcp --dport 1802 -j SNAT --to-source y.y.y.y

where x.x.x.x is a public ip of your server, y.y.y.y is the vpn ip of the server, and z.z.z.z is the vpn ip of where you are running fantasy grounds

You don't need a huge/powerful vps to do this, some of the $1 a month ones would work fantastically.

[Illmirranor]

Hi, everyone:

I'm trying to get FG set up on my home PC so I can host games but I can't get it to work.

I am virtually certain the problem lies with the Arris CM820 cable modem provided by my cable company, though they swear they are not blocking port 1802. I have a WIRED connection between by PC (running Windows 7) and my Linksys WRT54GL router. I'm confident I've set up a static IP address and port forwarding correctly on my router, but it's not working.

Would anyone be willing to help me troubleshoot? Also wondering if there is an easy way to test whether the modem is blocking the port. I'm wondering if I need to disconnect my router and plug directly into the modem so I can try to access the modem admin. (If the modem doesn't have the default password, I won't be able to get in.) In fairness, the modem does not seem to be blocking any other ports.

FG connection test fails. Also fails when I test port 1802 on canyouseeme.org.

Thank you.

[damned]

Send me your email address via PM and Ill have a look with you.

[Varsuuk]

If you can't get into the modem - do a google but I suspect there is a way to "Reset" to factory state (which is why you need to look at manual to find out what those are... some do admin/admin some admin/<nothing> others just about anything else...sorry) if you needed to go there.
Probably a good idea to reset it to a password your write down - when you have time to deal with the issues. Otherwise a day will come when you NEED to change something and blamo... no time to figure it out.

[damned]

Hi, everyone:

I'm trying to get FG set up on my home PC so I can host games but I can't get it to work.

I am virtually certain the problem lies with the Arris CM820 cable modem provided by my cable company, though they swear they are not blocking port 1802. I have a WIRED connection between by PC (running Windows 7) and my Linksys WRT54GL router. I'm confident I've set up a static IP address and port forwarding correctly on my router, but it's not working.

Would anyone be willing to help me troubleshoot? Also wondering if there is an easy way to test whether the modem is blocking the port. I'm wondering if I need to disconnect my router and plug directly into the modem so I can try to access the modem admin. (If the modem doesn't have the default password, I won't be able to get in.) In fairness, the modem does not seem to be blocking any other ports.

FG connection test fails. Also fails when I test port 1802 on canyouseeme.org.

Thank you.

This one was caused by a VoIP device in between the cable modem and the network router.
Once we moved the VoIP device behind the network router instead it all worked.

[Illmirranor]

Yes, and kudos to damned for helping me figure that out. The VOIP provider wanted their device between the modem and the router, but once we just plugged it into the router, everything worked just fine.

For some reason, though, I have to power cycle my router every time I reboot my computer before players can join. Not sure why that is, but my router is ancient. I'm planning to replace it soon and will post another note to this thread if that doesn't solve the problem.

[crankdawg47]

Alright guys I need help. Pulling my hair out here. Here's the story:

First, up until last week I had everything working while running windows 7 pro. However, I just upgraded my MOBO, CPU, and RAM which required me to install Windows 10 home. Then things stopped working (players can't connect to me)

I have set up static IP and modified the existing port forward on my router to reflect the new IP. (didn't work)
I changed my static IP to what it was before the upgrade and changed the port forward rule again. (didn't work)
Deleted the port forward rule and remade it. (didn't work)
Put my PC in my router's DMZ. (That worked)
Took the PC out of the DMZ and turned the router's firewall off. (didn't work)

At this point I have no idea where to go from here. I discussed this with one of my players who happens to be a network tech but even he is baffled. Below is a screen cap from my router. Any help would be appreciated.
Attachment 16783

[Nylanfs]

Check your AV and make sure it isn't blocking FG

Also, do you have a cable model AND a router?

[Trenloe]

@crankdawg47 - as it worked OK when your PC was in the router's DMZ, I think that your AV setup is OK - unless the network type changed when you put it in the DMZ. Just make sure that Windows sees the normal network as private (home or work).

Have you tried rebooting your router? Sometimes that's required to get any changes to port forwarding to stick.

[crankdawg47]

@crankdawg47 - as it worked OK when your PC was in the router's DMZ, I think that your AV setup is OK - unless the network type changed when you put it in the DMZ. Just make sure that Windows sees the normal network as private (home or work).

Have you tried rebooting your router? Sometimes that's required to get any changes to port forwarding to stick.

Currently using windows defender since avira was giving me other issues but I did check the network settings and found it to be set to public. I changed that to private (as seen below) but that did not fix the problem.
I did reboot the router after the first set of changes but haven't done so since the network type change on the computer.

Attachment 16791