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TOPIC: A few small Questions about NAT/Proxy/Firewall server

A few small Questions about NAT/Proxy/Firewall server 12 years 11 months ago #12808

I am running a network of 29 computers all connecting to the internet through a NAT/Firewall and some through a proxy running on the same server, others go around the proxy for internet connectivity.

I have run into a few problems so here is the background information on the setup:

It is a star type network running ethernet 100mbit.
The server is running 602LanSuite 2004 registered.
Server Hardware:
1.9 Ghz Duron
512 DDR 400
2x40 Gig HDD
2 PCI Network cards
Our shared internet connection is 1024Down/512Up 2 way satellite connection.
We are using Static IPs on the LAN, if we dont then I cant track peoples total bandwidth usage.

The problems I am having are that when mulitple people are using webcams and VoIP software there is a tremendous load on our connection. Originally I though we were just asking for more bandwidth than our connection could provide, as it turns out, we do not use that much bandwidth. When I have the horrible load on the connection no one on the network gets any information at all. I basically completely loose internet connectivity.

Also I was watching incoming packets on the LAN network card in the server and inbound/outbound packets on the Internet side of the server. They do not match, there are FAR more coming into the server from the LAN than actually make it out the other end to the internet. This makes me think that either
A: NAT is overloaded and the server ran out of ports to assign for translation or
B: There is some unknown (to me) limitation on how much traffic this computer can process at once.

The CPU load on the server stays low, 8%-20% at all times. The memory usage and page file are also not very taxed, about 1/2 most of the time.

Please excuse any eratta, as I am not by any means an IT, I am just a gamer turned admin trying to do my best with stuff I dont know very well.


Re: A few small Questions about NAT/Proxy/Firewall server 12 years 11 months ago #12822

hi claviger, with the description you have given us. i think your network is fine but they can can few loopholes as i see it now.

1. Try firewall setup and check the firewall settings.

2.Use of voips and webcams can really slow the network but as you mentioned its using only 20% of cpu and half of your server memory
so its fine but those (voip and web cam ) s/w are they same or r they different cause some times they can conflict.

(i think they is a conflict in the network thats why its down at that time 'try to find out that ').

3. last year i had a serious problem like this and found out its a bug in my system so def worth checkin.

4. the nat config, you did not mention it much. its the key issue here. check it wheather you set it right.

best of luck ':)'

Re: A few small Questions about NAT/Proxy/Firewall server 12 years 11 months ago #12830

Thankyou Cisman,
I know all of the Webcam software is trying to use the same ports:
5100, 5101, 5050, 5000. Mostly its yahoo messenger video stuff. The voip is an assortment of software spread across a ton of ports.

Re: A few small Questions about NAT/Proxy/Firewall server 12 years 11 months ago #12835

Ok after reading some more on, I find that the NAT I have is probably NAT Overload method and thats why its translating everything.

I also found that I can turn off NAT and the connection works, as long as the client is connecting through the proxy and not trying to go around it (when i say go around, I mean they have "direct connection" checked in IE instead of entering the proxy information).

However, I cannot get webcams/audio/games to work through this proxy, as it requires mapped connections. I have started to figure out and understand mapped connections, but I have to enter one for every port that I want to map, that is a ton of ports with all the people on my network using different software.

Is there a shortcut way to allow peer to peer connections such as gaming and webcams/audio without having to map them? It would have to be something run server side that the clients would not need to use.

My users are basically all AOL level idiots (not that I am much further ahead on networking :/).

Thanks again

Re: A few small Questions about NAT/Proxy/Firewall server 12 years 7 months ago #14877

is this skype software ? i know that skype can cause real issues with your firewalls, some firewalls see the requests as attacks and responds how it feels it should
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